The grand plan was this: to go on vacation.

A bit presumptuous in these tumultuous times, perhaps, but my girlfriend and I were both vaccinated, our passports were in order, and we hadn’t packed more than 3.4 ounces of any liquids. We’d fly from Newark to Rhodes, catching a connecting flight at Heathrow. We steeled ourselves for the British airplane food, but as it turned out that wasn’t even the worst of it. Here’s how I ended up on the C.D.C.’s Do Not Board list.

When we reached the airport, we were told that, in addition to a vaccination card, we would also need to prove a negative coronavirus test. This would be easy enough: all we had to do was head over to a testing center at an adjacent terminal. It was located outside, behind a bus stop. Luckily, there was no line. We were tested right away.

They called my name, and I approached the results window. My nurse took a look at her computer and said, with utmost tact, “When were you hoping to fly?” I told her I was hoping to fly in about two hours. She pressed a button and a piece of paper came slinking out of her printer. She circled something on the page, folded it, and slid it through the window.

“That’s not happening.”

I unfolded the paper and saw what she’d circled: a line of text that read, “POSITIVE!” In all caps. With an exclamation point. Circled—redundantly, I’d argue—in pen.

Needless to say, this was not the result I was hoping for—or expecting. I’d been working almost exclusively from home for the past year, wore masks outside, and had absolutely no symptoms at all. My one relief was that my girlfriend had tested negative.

The head of operations there, a man in ill-fitting khakis who looked—and talked—like a high-school football coach, took a knee next to me as I sat down, absorbing all this. He put a hand on my shoulder and looked me in the eye.

“Buddy, I get it,” he said. (He would go on to address me as “son,” “buster,” and “champ.”) “You’re pissed. You can’t believe this is happening to you. Who is that over there, your wife, girlfriend, wife? Girlfriend? You love her? You love her more than anything else in the world? Then you stay as far away from her as possible. Or else you’ll ruin the rest of her life, and yours, from the guilt.” He slapped me on the shoulder. My girlfriend and I smiled, nodded, and made for the exit.

We played it safe, immediately called friends and family we’d seen in the past 10 days, urged them to get tested, canceled our flight, and headed home to begin our isolation period.

On the way, I received a call from someone who introduced herself as “Anne from the C.D.C.” She asked me if I had just tested positive. I said I had. She hung up. She called again a few minutes later, asking me if I had canceled my flight. I said I had. She hung up again.

She called a third time, asking if I could text her a screenshot of my payment information from the ticket purchase and refund.

I was taken aback by that—it seemed hard to believe federal business could be conducted by screenshot—and asked if I could e-mail it to her instead. She said she didn’t have an e-mail. I was taken aback by this, too, operating as I was under the assumption that the C.D.C. had access to the Internet.

I asked if I could call the C.D.C.’s main line for further details on confirming my cancellation.

“Yes,” she said.

I’m a sucker for formality; I asked Anne for her last name, “so the C.D.C. can properly direct me to you when I call back.”

She said, “Uh, no last name. You can just ask for Anne.”

Confused by the day’s events though I was, I retained enough wherewithal to suspect there was a chance that the C.D.C. has more than one Anne among their number. The caller’s sketchiness (no e-mail? no last name?) exacerbated my skepticism. This time I hung up. Not only did it look like I had the coronavirus but apparently some phishing artist was trying to scam me.

“Buddy, I get it,” he said. (He would go on to address me as “son,” “buster,” and “champ.”) “You’re pissed.”

The next day, my girlfriend and I got tested not once but twice, each. Once with an antigen test and, again, with a P.C.R. test (the results of which we’d paid to expedite). All four came back negative. These new results seemed to prove that my test from J.F.K. had been a false positive!

Although neither of us had prior personal experience with this kind of thing, we had heard that you were able to “test out” of a false positive. In other words, if you had two tests that proved you did not in fact have the coronavirus, the previous false positive would be struck from the record.

The grand plan was back on. Greece (and the pitfalls of international travel) be damned, we booked a flight for Hawaii. (An island is, after all, an island.)

We found a flight for the very next morning, set our alarms, and went to bed early.

At 11:30 that night I woke up to a call from the federal government. The man on the other end said he knew that my girlfriend and I had booked a flight for the next morning.

He said, “Don’t even bother showing up to the airport. You’ve been placed on a do-not-fly list. If you were to try to board that flight tomorrow, we’d have to take next steps.”

Which is a sentence that stops you in your tracks.

This new caller—who provided a last name to go along with his first, as well as an official e-mail—informed me that although it had been the case that one could “test out” of a false positive in the past, this was no longer federal protocol.

“It was a very recent change. A lot of people haven’t heard about it.”

“Fascinating,” I said, now an enemy of the state.

I thanked him for his help, he thanked me for my cooperation, I told my girlfriend the bad news, and we settled in for our 10 days of seclusion.

All things considered, we’re lucky. We don’t have the coronavirus, nor do our friends and family. (They all tested negative.) We were able to get nearly all our travel expenses refunded. And, ironically, my non-vacation of a vacation ended up being Greek enough.

The islands we had originally planned to visit were associated with ancient Greek poets (Homer and Erinna), and I understand ancient Greek poetry to have two main themes. The first is hubris, pride coming before the fall. To wit, I might have done better to overprepare and get tested before the day of our flight so I wouldn’t have had to rely on the tests given behind the bus station at J.F.K.

The second main theme of ancient Greek poetry is the unpredictability of the gods, the sometimes harsh and funny (to others, anyway) role chance plays in our lives. Our grand plans mean nothing to Zeus, or to our global-health gods.

Michael Mungiello is a literary agent at Inkwell Management