AIDS was ravaging the theater community, and Mr. Finn knew that when he revisited the characters after the nightmare interval of the 1980s, it would have to play a part — even if, as he thought, “there’s no way I can measure up to the horror.”

The epidemic had not abated by 1992, when the combined “March of the Falsettos” and “Falsettoland” arrived on Broadway, repackaged as “Falsettos,” an idea first piloted by the director Graciela Daniele at Connecticut’s Hartford Stage.

The cast and crew had all been personally affected. Heather Mac Rae, who played Dr. Charlotte, remembered attending the funeral of a friend, the songwriter Paul Jabara (he wrote “Last Dance” for Donna Summer) in Brooklyn, then going straight to the theater for that evening’s show. Even the 11-year-old Jonathan C. Kaplan, who played Jason on Broadway, watched the voice teacher who coached him through his “Falsettos” auditions decline and die during previews.

“At that age, you don’t really comprehend exactly the ‘why,’ but you understand the ‘what’” of the disease, Mr. Kaplan said in an interview. “The family around ‘Falsettos,’ each had a personal experience of it. They had each lost someone. We were all in this together.”

It was no less affecting for the audience. “People were broken at the end,” said Stephen Bogardus, who played Whizzer. “You would sometimes come out through the house, and there would be people left in their seats, 10, 15 minutes later, just holding each other.”

Michael Rupert, who starred as Marvin, remembered AIDS patients in town for treatment waiting by the stage door. “All they wanted to do was be near us for a bit, to tell us how much this story meant to them,” he said. “I got a lot of letters from guys who were sick.”

The original run of “Falsettos” was a qualified success — it won Tony Awards for best score and best book, though it lost best musical to “Crazy for You” — but the acceptance depicted onstage was far from universal. When the cast and crew rode in New York’s annual Gay Pride Parade, protesters screamed at them in front of St. Patrick’s Cathedral.