Suppose you wanted to kill someone.

That would be easy. There are lots of ways.

But suppose you wanted to kill four people. All in the same house. All within moments of one another. And you chose to use a knife.

That could help eliminate the noise. But it would require skill, strength, and endurance. Murder is hard work, especially if people fight back.

Then there’s the really big obstacle: you want to get away with it. You’re determined to stab four people living in a single home in the still of the night and then disappear without leaving a clue to your identity. Now that’s a more difficult challenge.

But you did it. You have everybody stumped. It’s the perfect crime.

That’s the real-life mystery that had enshrouded the pretty northern Idaho college town of Moscow (pronounced not like the Russian capital but to rhyme with Costco, the locals, with no attempt at irony, quickly reprimand newcomers).

It had been a football Saturday in mid-November, the last home game of the 2022 season for the University of Idaho Vandals, the Kibbie Dome packed with more than 7,600 fans. And despite the disappointing loss, Saturday night was still party night for a college celebrated in knowledgeable polls as “the best party school” in the state.

The stately row of “wet” frats (as they’re known on the U of Idaho campus) twisting along Nez Perce Drive was crowded with the brothers and their dates, high-spirited assemblies fueled by blaring music, prospects of mischief, and rivers of alcohol. (The Hellenic Council, for reasons arcane and firmly sexist, prohibits liquor to be served in sororities.) Downtown, Main Street was hopping, too; the pool tables at Mingles and the metal-sheathed bar at the Corner Club were shoulder to shoulder with students and townies filling the brisk autumn night with the keen of cheery, rowdy late-night fun.

The scene of the crime: an off-campus house on King Road.

And then in the heavy quiet of the new Sunday morning, four young corpses, all students, all friends, were found hacked to death in their beds in a pale clapboard house little more than a stone’s throw away from the heart of the university campus. There was so much blood, it had seeped through the wooden floors and run down the building’s gray concrete foundation in jagged red rivulets.

It wouldn’t be until nearly seven tense weeks later when an early-morning raid by a police SWAT team thousands of miles away from the scene of the crime finally arrested a suspect. Bryan Kohberger, a 28-year-old doctoral candidate in the Criminal Justice and Criminology department at Washington State University, was pulled from his parents’ home in the rural Pocono Mountains of Pennsylvania and charged with four counts of first-degree murder and one count of felony burglary.

Yet even with the arrest, mysteries remain. Neither reasons nor motives have been revealed that would explain the horror that ended four lives. And in the unhealed aftermath, there remains an armory of fears, 25,000 people in a once seemingly bucolic town nestled in the rolling snow-swept Idaho hills still alert with suspicions, neighbors seared by the mystery of four perplexing deaths, victims who have left them victimized, too.

Something Ominous

Later, when it became necessary to fix blame for the initial confusion over the gravity of the situation, fingers in the Moscow police department pointed to the dispatcher. But the truth is, the dispatcher was simply following procedure.

All the town’s 911 calls are routinely routed to Pullman, about 10 miles west in Washington State (and home to Washington State University), where they’re handled by the civilian employees of a municipal agency called Whitcom 9-1-1. The calls come in from the local Whitman and Asotin counties, as well as the city of Moscow, two universities with a total of about 42,000 students, and 70 additional municipal and county agencies. And the dispatch crews, local newspapers report, are severely understaffed. The overtime schedules often add up to a grueling 20 hours each week. In fact, the dispatchers’ guild has complained that “our ability to uphold public safety is at risk.”

And things only get worse on football weekends. Therefore, when the callers are agitated, rather than risk injurious delays by probing for details, the responders swiftly assign a generic explanation. “Unconscious person” is one of the standard catchphrases. It can mean precisely what it says, or it can be shorthand for something more ominous.

It was 11:58 a.m. on Sunday, November 13, 2022, when the notification of an “unconscious person” at a residence on 1122 King Road, Moscow, was passed on to Sergeant Shaine Gunderson. Gunderson, who on that day was midway through a 12-hour shift that had started at six a.m., was running the Operations Division at the sparklingly modernistic—it had opened barely 11 months earlier—Southview Avenue police headquarters.

Officer Shaine Gunderson was among the first at the scene after the 911 call came in.

Prior to that moment, he’d tell people, his tour had been long and slow, a languid weekend morning punctuated by the chimes of the town’s many church bells tolling solemnly in the wind. In fact, he’d spent a good deal of that desk-bound Sunday mulling something other than police business. Gunderson had been avidly mapping out in his mind a strategy for the eight-hour (or easily more!) trek to the summit of Mount Borah he and a friend from the University of Idaho psych department had been planning for the spring. It’s Idaho’s highest point, and the trail up the Southwest Ridge to the 12,662-foot summit is a steep, hard climb. And, he’d admit after a beer or two, it was just the sort of challenge he’d been missing lately.

Now that he had his sergeant’s stripes, police work was more about distributing memos and filing papers than getting out into the field. That bothered him. Nearly 10 years on the force, he still wanted to be the gung-ho officer who had joined up straight out of Lewis-Clark State College, in nearby Lewiston, and worked his way up from patrolman. In his early days, he’d distinguished himself as a hands-on cop, someone out in the streets doing what the Moscow P.D. calls “community policing.”

Back then, he’d scored a lot of points both in and out of the department (as well as winning the Officer of the Year honor in 2017) when he single-handedly planned and organized a hot-dog barbecue bringing together the cops and local school kids. He was from the area, growing up in small-town Potlatch, and, still smarting from his own childhood run-ins, he knew only too well how hard-ass cops could sour things, make things confrontational. It was his job, he’d say with determination, “looking out for and working with the citizens of Moscow.”

When the 911 came in, Gunderson had a corporal and two other officers on duty to assist with patrol. He could have left the response to them. He certainly, he’d tell people with a hint of embarrassment, had no intimation of something out of the ordinary. That morning he was simply eager to break the monotony. And, as always, he felt strongly it was important for him to get out on the street where people could see him. He swiftly decided he’d go to the scene, too, with his officers.

An Eerie Silence

It was a quick trip. The roads leading into the university neighborhood that Sunday were as empty as the classrooms. And as soon as Gunderson’s black-and-white cruiser pulled up behind the neat row of cars parked in the driveway of the austere cantilevered house on King Road, he immediately knew something was very wrong.

It was the noise: there wasn’t any. Just an eerie, unnatural silence. A cluster of young people, university students presumably, were milling outside the open front door of 1122 like gulls on a beach. And yet they were exceptionally quiet. They weren’t merely subdued. They seemed stunned, as if drained by a deep and intense shock. When the three mystified officers approached the front door, someone in the crowd, it would later be shared, muttered a single, plaintive word: “Dead.”

Still, Gunderson would confess to others, he was unprepared for the strong smell of blood that rose up in his nostrils the moment he walked inside. The coroner, who had once been an emergency-room nurse in an earlier stage of her life, would describe the scene in press interviews as “chaos,” “lots of blood.” Few others would even attempt to put into words what they saw.

There are moments, cops will tell you, that are too profound, too unnerving, to be experienced in the present. All you can do is move forward; there will be time later to try to make sense of it all. Procedure takes precedence. It allows a protective membrane to be stretched between the real and the too real. All other thoughts, all other feelings, become extraneous.

There was so much blood, it had seeped through the wooden floors and run down the building’s gray concrete foundation in jagged red rivulets.

And so, Gunderson and his two officers, largely mute, almost robotic in their movements, now stepped carefully across the blood-streaked wooden floor and proceeded to inspect a crime scene. Wedged against a hill, the house rose up on three distinct levels from a platform base like an ancient Persian ziggurat. The officers set out to inspect each floor. They moved cautiously, not knowing what they’d find. Yet, of course, by now they knew.

The first floor, nevertheless, was a surprise. There were two bedrooms, and when they anxiously entered each one, there were no signs of anything out of the ordinary. Later they would learn that the two university-student occupants, Dylan Mortensen and Bethany Funke, had apparently slept obliviously through the carnage. It was an explanation that made no sense, unless one’s life had been informed by the experience of being a college student who’d curled up in bed after a long night of drinking.

Victims Ethan Chapin and his girlfriend, Xana Kernodle, both 20.

However, as the staggering day wore on, Mortensen would reveal more about what had happened that night. She told the authorities she had heard crying, opened her bedroom door, and saw a man in black clothes and a mask walking past her. “Frozen” and in “shock,” she stood immobile as he headed toward a sliding glass door at the back of the house. And then, inexplicably, she returned to her room and locked her door till the morning.

But in the daylight, things turned frantic. Mortensen and Funke first stirred from their beds sometime after 11 a.m.; they found it impossible to rouse their roommates and called friends for assistance; and then in the torrents of confusion after the friends had arrived, one of their cell phones was used to make the agitated 911 call that resulted in the “unconscious person” message which was relayed to Gunderson.

The trio of officers, meanwhile, proceeded with haste to the second floor. They opened the bedroom door to find two dead bodies, a male and a female. The pair was gruesomely drenched in blood, yet both their good-looking faces had, oddly, been preserved like masks. Even at that probing moment, it was difficult, one of the young officers would later nearly wail, to look at the 20-year-old pair—Xana Kernodle, a grave, sad-eyed beauty who was a Pi Beta Phi, and her happy-go-lucky, tousle-haired Sigma Chi boyfriend, Ethan Chapin, a triplet from Conway, Washington, whose surviving brother and sister also attend the university—and not consider the glow of the once rich promise that had been so viciously extinguished. (At her high-school graduation, in Post Falls, Idaho, Xana had confidently written on her mortarboard, “For the lives I will change.”)

Madison Mogen and Kaylee Goncalves, both 21, were found lying in a single bed on the third floor.

On the third floor things got, if possible, worse. In one bedroom, lying in a single bed, were two inert women, Madison Mogen and Kaylee Goncalves. They might have been sisters, so similar were the 21-year-olds’ pretty Barbie doll–like sculpted features, their long cascades of thick, streaked blond hair falling down to their narrow shoulders. Yet in death there was one gruesome difference: Kaylee, it would be reported, had been hacked with a particular ferocity. It was as if her wild assailant—or was it assailants?—had been intent on gouging out chunks of her flesh. “Large punctures” was how the lacerations had been described. Maddie’s wounds, while no less fatal, appeared less feral, more measured—at least in comparison.

Across the narrow hallway was one final door. The officers pulled it open. And at last they discovered a sign of life: a fluffy caramel-colored dog. It was Murphy, Kaylee’s frisky Labradoodle. He was unharmed, not marred by even a speck of blood—a small consolation, and barely one at that, for all they had seen and were only beginning to process.

A Major Case

And it was still the same long day. Of the frenzied moments and then hours that followed on that seemingly interminable Sunday, there is only so much that can be authoritatively reported. Even Gunderson and his team lost track of all their efforts in the hectic swell of events. Yet this much is undisputed:

Gunderson quickly called his boss, Captain Roger Lanier, the head of the 24-officer Operations Division. He found him, not unexpectedly for a Sunday, sitting down to lunch with his family. Lanier was a veteran cop; he had spent more than 20 years on the force in nearby Lewiston before having been lured, six years earlier, to Moscow with a captain’s rank. After all his years on the job, he’d become a steady, avuncular presence, a bald-headed genial cop who never got flustered because, as he’d tell people, he’d seen it all in his day.

But Gunderson’s report left him unnerved. “It took me a second,” he recalled, a sharp edge, even weeks later, to the memory. “I really had to think about what I had just heard. Four murders in Moscow, Idaho, was so out of character.”

But quickly Lanier’s professionalism took control. He had a thousand questions, and yet he knew the only hope of finding answers would be to follow the previously established protocols. Dutifully, he gave the orders to set up the perimeters of the crime scene, to bring in the forensic team, and to summon the coroner. It was standard in a major case—and if four homicides wasn’t a major case, what was?—to alert the Idaho State Police, and he did that too.

Captain Roger Lanier had more than 20 years’ experience as a police officer, but Gunderson’s report left him unnerved: “Four murders in Moscow, Idaho, was so out of character.”

Moscow was the responsibility of the state’s District 2 Detective Office in Lewiston, the county seat and where he’d been on the job for two decades, and he knew many of the state detectives. There was a companionship. Still, it was a difficult conversation.

But his next call was harder. The university had to be informed. It was not just that four students had been brutally murdered in an off-campus home, but there was no way of knowing whether the killer—or killers—planned to strike again. The students needed to be warned.

At 2:07 p.m., a little over two hours after the three cops had entered the blood-soaked house, the University Office of Public Safety and Security sent a “Vandal Alert” e-mail to the students and faculty: “Moscow PD investigating a homicide on King Rd. near campus. Suspect is not known at this time. Stay away from the area and shelter in place.” A “shelter in place” order requires people to “take refuge in a room with no or few windows.”

At this point, busy hours had already quickly flown by. But despite his marathon of activities, Lanier still had not succeeded in completing one task that was at the top of his mental list: he had not been able to speak with his boss, James Fry, the chief of police.

A Buried Memory

The chief had been getting death threats. He’d counted six, a virulent collection of unsigned letters and barking phone messages emphatically promising he’d be killed. And those missives were in addition to the tall pile of rude and scatological, although less murderous, e-mails and notes he’d received.

The ostensible reason for these threats? He had ordered his officers to enforce the mayor’s and the city council’s coronavirus restrictions. People had received summonses for not wearing masks in public. And at a defiantly maskless prayer vigil in the City Hall parking lot, several of the more reverent in the open-air assembly had been cuffed and hauled off on Fry’s orders. His no-nonsense policing had made the chief a lot of enemies.

The municipal restrictions ran counter to the deep-seated, self-reliant pioneer spirit of many Idahoans. And, no less a force of enmity in the town, there was a very active (and rapidly growing) archly fundamentalist congregation at Pastor Doug Wilson’s Christ Church, which not only saw masks and vaccinations as counter to “God’s teachings,” but also held that “our local city government, law enforcement included, is a nest of incompetence and corruption.”

But by the fateful November weekend when the murders occurred, Chief Fry had hoped that all the bad feelings that’d been simmering in the town over the past two years had, with the end of the coronavirus restrictions, also largely slipped away. The previous spring he had missed his chance to go on a prolonged elk hunt; he hadn’t felt right about leaving Moscow for too long. But he no longer had such qualms. On November 12, Fry and his wife, Julie, had driven to visit a friend nearly three hours away.

Moscow police chief James Fry has received death threats for his enforcement of local pandemic restrictions.

By the time Lanier had finally reached him, it was hours after the discovery of the bodies. And by the time Fry finally entered the home on King Road, it was dark outside—according to several accounts, close to six p.m. For some abstruse reason, he’d thought it was important to go home first and change into his chief’s uniform. Perhaps he hadn’t fully grasped the magnitude of the disaster. Or maybe, after nearly 28 years as a Moscow cop, he had felt the imprimatur of his uniform was integral to his ability to command.

But what he saw that evening left him, he would confide to a friend, “physically and emotionally drained.” He was a father of two daughters who had attended the University of Idaho, and he had also graduated from the university nearly three decades earlier. It was impossible, he said, not to feel a visceral tie to the victims, and to their parents. The cruelty of the crime was deep and affecting. And yet, he knew, there was police work to be done. His mind was racing, but, quixotically perhaps, within moments a buried memory pushed itself forward.

There was no way of knowing whether the killer—or killers—planned to strike again. The students needed to be warned.

Three years earlier Fry had been chosen to attend the 10-week course at the F.B.I.’s National Training Academy in Quantico, Virginia. He was on the cusp of turning 50, and the impending milestone, he’d confided to a close friend, had triggered a soul searching. He’d wanted to prove that even as he was acknowledging the inevitability of his soon becoming a senior citizen, he was still the sort of cop who could break up a bar fight or strap on SWAT gear when some local went berserk and started shooting up the courthouse. A chief goes to lunches at the Chamber of Commerce and plays golf with the mayor. Fry wanted to show he still could be more. His friends called him “old-school,” and it was an appraisal that had always sat well with him.

So, it had been very important to Fry to complete the 6.1-mile obstacle course at Quantico called “the Yellow Brick Road.” The signs nailed to the tree at the starting line read Hurt, Agony, and Pain. There was climbing over walls, crawling under barbed wire, sloshing through streams, hauling up steep cliffs, and running full speed through rocky, winding trails.

And Fry did it. The certificate he received in recognition of this accomplishment is displayed with pride across from his desk in headquarters. It was what he first talked about when he talked about his time with the F.B.I.

But on this unsettling evening another memory reached out to him. A day or so before he’d taken on the Yellow Brick Road he had been to a class led by a member of the F.B.I. Behavioral Science Unit. The lecturer had explained how the bureau had been able to get into the heads of killers. They had studied what made them kill, and how to catch them before they would kill again.

A makeshift memorial for the murdered students.

What if, Fry asked himself with a sudden alarm, a serial killer had attacked the four students?

Fry called the bureau and asked for their assistance. It was quickly arranged. A team of agents, eventually about 40 in total, would be dispatched to Moscow; a smaller group, flying in from the Salt Lake City office, would be arriving as soon as tomorrow. And as he’d specifically requested, three members of the Behavioral Analysis Unit, two men and a woman, were also being dispatched.

Fry, however, wasn’t done yet. He had been working restlessly through the night, but with the dawn of the new day he realized there was something he’d forgotten.

When Rand Walker got the call, he was in his GMC pickup heading down the twisting 700-foot driveway that led from his house to the main road into town. He looked at the caller ID and figured he knew why the chief was calling first thing in the morning. His friend wanted to apologize.

A week or so earlier, Walker along with his band had been playing at Bucer’s Coffeehouse & Pub downtown. They performed 70s cover songs, a lot of Eagles, a lot of Van Morrison, and their version of Neil Diamond’s “Sweet Caroline” was a get-out-of your-seat favorite. They had quite a following in northern Idaho. And the chief had promised to be there, only he’d never showed.

“No problem, chief,” Walker began breezily. “I know you got plenty to do. You’ll catch us next time.”

“It’s something else,” Fry said curtly. “I need you to stand by.”

Immediately Walker knew something awful had happened. A Ph.D. with a private practice in Moscow, he also served as the department’s psychologist.

“Some of my young officers are gonna need your help,” Fry continued. Then he corrected himself. “Actually, it’s not just the young ones.”

A Different Sort of Predator

The wolf had gotten away. It was spring break 2010, and Brett Payne, a 20-year-old University of Idaho student, had been determined to bag the big gray wolf that had been seen roaming up on Lindstrom Peak deep in the high timber of northern Idaho’s St. Joe National Forest. Only, after four days, Payne hadn’t even found a single paw print.

When Payne broke camp that morning, he considered giving up, but in the end it just didn’t feel right. So he kept at it, and at about four p.m., the sun still high in the sky, he spotted tracks. He followed them for the next two hours.

And there it was: a big male wolf laying across a draw in the middle of the road, about 300 yards in the distance.

Payne quietly fell to the forest floor. He could see the animal clearly through his rifle scope. If the wolf caught a human scent, he’d bolt. But the wind was in Payne’s favor.

Officer Brett Payne led the morning briefings during the frustrating, weeks-long investigation.

He put his finger on the rifle’s trigger, started to apply pressure, yet still hesitated. “It was intense,” he later explained. He needed to calm down.

But suddenly the wolf raised his head, so Payne shot. The bullet went through the wolf’s chest, dropping it at once. Payne had bagged his wolf.

It was now 12 years later and Payne was once again the relentless hunter. Only now he was on the trail of a different sort of predator. He was the lead police investigator in the four King Road homicides.

Payne had come to the Moscow P.D. just two years earlier, after serving in the 82nd Airborne Division in Afghanistan and a stint Stateside in the M.P.’s. Chief Fry had taken an instant liking to his squared-away military demeanor, and promoted him quickly to corporal over other, more experienced officers. When the state police had asked who’d be leading the morning briefings, Fry, without thinking too much about it, chose Payne.

For one thing, the chief knew that the young corporal had been involved in several complex forensic investigations with the M.P.’s. That sort of technical expertise, the chief suspected, could come in handy. And for another, Fry had heard the story about the wolf. The chief, an old elk hunter, had come to appreciate that tenacity was half the battle in any hunt, maybe more.

And so nearly every morning at seven a.m. in the weeks following the murders, Payne would be up at the front of the conference room in police headquarters leading the case briefings. The room was big, filled with rows of polished blond wood tables sitting on a gray patterned carpet. Ceiling lights kept things very bright, and there was a band of small rectangular windows running in a row near the top of a side wall that let in light, too. Everything looked brand-new, and very corporate, as if a mid-level insurance company had just moved in. But there was a murder board up front with rows of gory homicide photos, and everyone in the room had a gun.

Clockwise from top left: Mogen, Chapin, Kernodle, and Goncalves.

The conferences would begin with a recitation of what the investigators knew. It was not a long list. Consider:

Fact: The four students were killed in their sleep, sometime between three and five a.m. (In the weeks ahead, they’d develop a more precise timeline: the murders, the authorities deduced, occurred between 4 and 4:25 A.M.)

Fact: There was no sign of forced entry, or of robbery.

Fact: A single weapon had been used—a long-bladed knife. And a tan leather knife sheath, stamped with the U.S. Marine Corps insignia, was found lying next to Mogen’s bed.

Fact: There was no trail of blood outside the house.

Fact: The house was a repository for a large collection of forensic evidence—blood, saliva, hair, prints, DNA. But whether any of these belonged to the killer—after the autopsies, the general consensus held that it was a single assailant—still was undetermined.

These were all, the investigators agreed, important pieces in the puzzle. Yet they were not enough. For more than three weeks, the early-morning conferences ended in a grim litany of what remained unknown.

They couldn’t figure out how the killer had gotten away seemingly without leaving a clue. And they had no idea why he had chosen these victims.

“A Weird Feeling”

It was Arthur Conan Doyle back in 1887 who first introduced the role of a “consulting detective.” “Here in London,” Doyle’s ingenious hero Sherlock Holmes boasted, “we have lots of Government detectives and lots of private ones. When these fellows are at fault they come to me, and I manage to put them on the right scent.”

And now as the investigation in Moscow plodded on and frustratingly on, an exasperated Chief Fry appealed to locals to become, in effect, “consulting detectives.” He wanted help to put his men “on the right scent.”

“Detectives are looking for context to the events and people involved in these murders,” a Moscow P.D. press release announced. “To assist with the ongoing investigation, any odd or out-of-the-ordinary events that took place should be reported.” And nearly begging, the release urged, “Your information, whether you believe it is significant or not, might be the piece of the puzzle that helps investigators solve these murders.”

The tips poured in. A new generation of consulting detectives armed with cell phones and laptops, with access to a vast repository of information, from selfies to Facebook pages, and further stoked by the barrage of the raw theories and hearsay disseminated on Reddit and 4chan, embraced the opportunity. It was a real-life mystery that had the compelling allure of a particularly thorny C.S.I. episode. And, not least, the police were pleading for help.

Students and faculty at the University of Idaho remain shaken by the events.

By a recent count, more than 9,025 e-mail tips were received, in addition to 4,575 phone calls and 6,050 digital-media submissions. An army of law-enforcement analysts was assigned to the long, daunting task to see if in all the oysters there was a single pearl. It was the back-bearing of all time. Much of it led down rabbit holes of fatuous speculation.

Some was not just wrongheaded but cruel. Innocent ex-boyfriends; a hoodie-wearing bystander lurking at a food truck where Maddie and Kaylee had ordered early-morning bowls of carbonara to soak up the alcohol ingested during the last carefree pub crawl of their lives; a bro neighbor who insisted on sharing rambling anecdotes with every reporter who knocked on his door; and frat brothers who were rumored to be stoked up on steroids and driven by long-gestating grievances—all were callously and persistently slandered with a malicious authority. It got so madcap that a history prof at the university decided she had to sue to put an end to one Internet sleuth’s bizarre speculation that a failed romance with one of the women had driven the teacher to kill.

And then the analysts hit a gold seam.

For more than three weeks, the early-morning conferences ended in a grim litany of what remained unknown.

The overnight assistant manager (her name, at her request, remains secret) for a gas station on Troy Road not far from the house on King Road had decided she might as well see what she could do. She had not been working the night of the murders, but nevertheless she spent the downtime on her graveyard shift reviewing the videos recorded by the station’s surveillance cameras on November 13. “I had a weird feeling,” she later said.

For two nights, she intermittently kept at it but found nothing. Then on the third night she spotted a white car speeding down Highway 8, before turning pell-mell down a side street. She took a screenshot of the car and e-mailed it to the tip-line address.

Two days later Moscow police arrived at the gas station to confiscate hours of surveillance footage. And after just a quick view, they began to feel the hunt was at last on.

Encouraged, they reached out on a hunch to Kane Francetich. Francetich, recently retired and now investing in real-estate, was a freewheeling guy who shares on his Web site that he “listens to classic vinyl while drinking single malt scotch.” He also owned a six-unit rental complex on Linda Lane, about three-tenths of a mile from where the bodies had been found, with a surveillance camera fixed to the roof.

The horrors mounted as the officers inspected each succeeding floor.

“I downloaded it and gave them access to everything from two A.M. through noon on that Sunday the 13th,” he said.

Once those tapes were reviewed, the same tell-tale white car was spotted. And again it appeared to be making a breakneck getaway through the dark three a.m. streets. With this confirming sighting, a different pace, a different mood took over the investigation. The team felt they could now march forward with a purpose. The F.B.I. laboratory enhancement had succeeded in deciphering the blurred image of the car. It was a white 2011 to 2013 Hyundai Elantra.

There were 22,000 Hyundais in the region that matched the search criteria.

And one of them, the police were starting to suspect, had been driven by a killer.

Only, finding the one Elantra that would lead to an arrest loomed as a needle-in-a-haystack sort of challenge. The search, even with a small army of burrowers, was a nearly impossible task. Then, as the holiday season approached, there was a hint of a Christmas miracle.

Chief Fry, for once upbeat, met late in the morning of December 20 with Rand Walker, the department psychologist, and Rod Olps, one of the police chaplains, in the Courthouse Law Library. It was one of the few places they could huddle where the chief felt no one would be listening.

“I’m gonna need you two to get ready,” he said with a deliberate coyness. “I’m gonna need you before too long.”

The two men eagerly asked whether there had been a break in the case.

Fry did his best to rein in a pregnant smile. “All I’m saying,” he reiterated, “is I need you both to stand by. I might be calling you very soon.”

But at 4:30 that afternoon, the Moscow Police Public Communications Team issued a Flash update: “Investigators are aware of a Hyundai Elantra located in Eugene, Oregon, and have spoken with the owner … the vehicle … is not believed to have any relation to any property in Moscow, Idaho or the ongoing murder investigations.”

And just like that, the psychologist and the chaplain knew that the chief, despite the hopeful conversation earlier that day, would not be calling them anytime soon.

An Icon of Horror

Meanwhile, as the hunt for the Elantra proceeded with tedious concentration, the no less discouraging challenge of finding a clue in the forensic evidence—a vast muddle of prints, blood, and DNA—that had been collected in the house was brought vividly home. Body-cam footage was released of a call at the King Road residence two months before the murders by a trio of Moscow cops in response to a noise complaint from an annoyed neighbor.

At first view, the footage was deeply poignant. The house seemed to be nearly shaking with festive noise. Tyler Childers’s “Feathered Indians” boomed from the speakers. Kids were calling happily to one another, a giddy mix of bouncy, energetic voices. It was a Thursday night and there was a party going on. This is what it’s like to be young.

To more acerbic minds, the footage was a small self-contained story about the tensions of policing in a college town. The kids, being kids, were seen giving the police a sly runaround. And the cops, being cops, retaliated with a display of petty vengeance: a confiscated stash of beers and Trulys was poured onto the driveway. (Yet this being Moscow, and this house being destined for infamy, this burst of class warfare would have an unexpected coda: one of the smirking cops spilling the booze would in time be part of the team that first discovered the bodies; another would help load the cardboard cartons holding the murdered students’ belongings into a U-Haul for the grim trip to the police parking lot.)

When the university notified the student body of the homicide investigation, its Office of Public Safety and Security issued a “shelter in place” order.

To the informed and dispassionate view of the F.B.I. scientific experts, however, the body-cam footage was seen solely in operational terms. And it was dispiriting. It made clear that just about anyone and everyone had access to 1122 King Road. The door was always open, and a stream of people were constantly coming and going. The analysts moaned that there would be so much forensic evidence, it might be easier to determine who in Moscow had never been inside the house rather than their having any realistic hope of ever finding a suspect.

This body-cam footage jumps up in my mind, too, as I stand across from the house on a dark, cold night late in December. The sky is gray, heavy with the promise of snow, and the pale, flat-colored house nearly disappears into this monochrome. The street is impossibly still; there are no extraneous sounds in the night. I try to imagine the house as it was in the video, something vibrant and energetic. Tonight that is impossible. All I see is a scene painted in grisaille. An icon of horror.

Suddenly, I am trapped in a very bright cone of fierce white light.

I am taken by surprise—stunned, in fact. And my first startled, terrified thought: This is what it might have been like to have been awakened without warning from a deep sleep. And to find yourself staring at someone raising a knife.

And then I hear a voice. “You gotta be careful there. It’s icy.”

A black security vehicle had been parked kitty-corner to the front door of the house, the car concealed by the dark shadows. And the officer at the wheel, I now realize, had illuminated the auxiliary spotlight mounted on his door, pinning me in its harsh glare.

“Thanks, officer,” I answer. “I’ll take care.”

And then I’m heading off, walking absently in the darkness out of the gulch and moving uphill. In the cold, my dark stocking cap pulled low on my forehead, my hands shoved deep in the pockets of my parka, I find myself standing on a flat, grassy ridge on Nez Perce Drive. It’s adjacent to the fraternity house where Ethan and Xana partied on their last night together. And now the snow has started to fall, a torrent of big thick silver and dark flakes.

From my vantage point, I can look down at the house on King Road and see the snow has begun to cover it. The same falling snow that I know is also blanketing the old red-brick university buildings, the bars on Main Street, the roads that twist through the humpbacked northern-Idaho hills. And the final resting places of the four dead students. And at that moment, watching the snow thickly descend, a fresh white sheath, I cannot help but despair that the solution to the mystery that has agonized this small town will be forever hidden, too.

Bryan Kohberger, a 28-year-old criminology doctoral candidate at Washington State University, has been charged with four counts of first-degree murder.

But I am wrong. For even as I am standing on that high plateau, a white Hyundai Elantra, albeit the 2015 model, not one from the years cited in the police bulletins, is making its way east from the snows of Idaho. Its journey started in a parking lot outside a graduate-student housing complex at Washington State University in nearby Pullman, just eight miles from my perch. At the wheel is Bryan Christopher Kohberger, and beside him, intriguingly, is his father. And all the while the F.B.I. has been covertly following along, too. The hunted and the hunters were heading to an early-morning rendezvous at a house deep in the Pennsylvania woods.

For the case has been solved, or so the authorities believe. The white speeding car in the Troy Road gas station video was one clue that had led them to Kohberger. And despite the odds, from the chaos at the murder scene, the technicians succeeded in extracting a tell-tale sample of DNA from the knife sheath. On December 27, Pennsylvania law-enforcement agents covertly rummaged through the trash at the Kohberger family’s white colonial house in Albrightsville. When items in the trash were analyzed in the lab, alarm bells started ringing: the matches to the DNA on the sheath were nearly identical to Michael Kohberger, the suspect’s father. This final piece completed the puzzle. An arrest warrant was issued for Bryan Kohberger.

And what about the suspect? Here is what we know so far: a pudgy child and adolescent, a teenage taste for heroin which he has allegedly conquered, a tendency to be rude and boorish in social situations according to the complaints of those who crossed his path over the years, and, not least, a fierce intelligence revealed in both college and grad-school classrooms.

He has agreed to be extradited to Idaho, and on January 3 he appeared in a Monroe County, Pennsylvania, courtroom. He first looked, at least to my eye, daunted by events, a sad figure in a red jumpsuit, cartoonisly bulked up by the bulletproof vest the authorities had insisted he wear underneath. Still, he is also a big man, long-armed and limber: a presence. And in the course of the brief hearing he appeared, again to my admittedly distant view, to grow more confident. A fierce, purposeful determination is, I decide, revealed. And I wonder: Does Kohberger, a man who seems to see himself as the smartest person in the room, have some legal trick up his sleeve?

He will stand trial in Moscow on four counts of first-degree murder as well as burglary. But even before his journey West, Jason LaBar, his court-appointed attorney in Pennsylvania, is fighting back. “Mr. Kohberger is eager to be exonerated of these charges and looks forward to resolving these matters as promptly as possible,” he insisted in a statement released to the press. “Mr. Kohberger has been accused of very serious crimes, but the American justice system cloaks him in a veil of innocence. He should be presumed innocent until proven otherwise—not tried in the court of public opinion.”

Yet while much remains to be sorted, it is clear that one corner of Kohberger’s life has been lived as a graduate Ph.D. student in criminology, someone who has conscientiously studied the vagaries of evil. In fact, in his purposeful search for knowledge he had sent out a research questionnaire to convicts asking for their help.

Kohberger was extradited earlier this week from his home state of Pennsylvania to face trial in Idaho.

“I am inviting you to participate,” Kohberger wrote, “in a research project that seeks to understand how emotions and psychological traits influence decision making when committing a crime. In particular, this study seeks to understand the story behind your most recent arrest, with an emphasis on your thoughts and your feelings throughout your experience.”

Was this simply a grad student’s academic inquiry? Or was a would-be killer asking the professionals, Suppose you wanted to commit the perfect crime, how would you do it?

And now, under arrest and awaiting trial, has he quite possibly discovered that there is no such thing as the perfect crime?

Howard Blum is the author of several books, including The Spy Who Knew Too Much: An Ex-CIA Officer’s Quest Through a Legacy of Betrayal