Consider it official: Fellow Travelers, the opera, has legs. Based on Thomas Mallon’s novel of 2007 and scored by Gregory Spears to a libretto by Greg Pierce, this swift-moving and affecting love story premiered in Cincinnati in 2016. Audiences there embraced it, as did the critics—one prominent early reviewer going so far as to name-check La Bohème. That said, forget the Latin Quarter of antique picture postcards. Fellow Travelers whisks us to the Washington, D.C., of the 1950s, at the peak of the “lavender scare.” Senator Joseph R. McCarthy, who appears in the opera, is riding high as Grand Inquisitor of his infamous House Un-American Activities Committee witch hunts. Scene One takes place on a park bench in Dupont Circle, where two strangers strike up a conversation that will change their lives romantically, professionally, and in other ways. Timothy Laughlin, a recent college grad, has just come to town, all set to fight the Commies. Hawkins Fuller, a State Department official with connections, gives Tim a referral that lands him a job in a senator’s office. Kevin Newbury, who staged the original production, takes the driver’s seat again for the Seattle revival—stop #1 on a multicity, multiseason tour. As Tim, Colin Aikins alternates with Andes Acosta; as Hawk, Jarrett Ott does the same with the role’s originator Joseph Lattanzi. The orchestration of Fellow Travelers calls for just 17 players, but the writing is skillful, suggesting the expansiveness of grand opera as well as the transparency of chamber music. Steven Osgood conducts. —Matthew Gurewitsch