On a cold, snowy night in January 1977, Sal Piro waited in line outside the Waverly Theater in Greenwich Village to see “The Rocky Horror Picture Show” for the first time. A campy science-fiction/horror musical whose characters include the cross-dressing mad scientist Dr. Frank-N-Furter, it had been developing a following for its Friday and Saturday midnight showings for several months.
Mr. Piro didn’t know much about the film, which follows a couple (played by Susan Sarandon and Barry Bostwick) as they seek help at Frank-N-Furter’s castle after their car gets a flat tire. But he was impressed that one of his friends had already seen it 19 times.
“So we got in line, made friends with some of other people on line and, once inside, we were both amazed and gobsmacked and under its spell,” the songwriter Marc Shaiman, a friend who was with Mr. Piro that night, recalled in an email.
Mr. Piro remembered his excitement at seeing the giant disembodied red lips that open the film with the song “Science Fiction Double Feature”; the infectious “Time Warp” dance; and Tim Curry’s dramatic entrance as Frank, singing “Sweet Transvestite.”
“Image followed image and the impact on me was tremendous,” Mr. Piro wrote in “Creatures of the Night: The Rocky Horror Picture Show Experience” (1990), one of three books he wrote or co-wrote about the film. “I began living the movie as it unreeled.”
Fans like Mr. Piro soon became fanatics. Showings turned into extreme exercises in audience participation. They dressed as the characters. They shouted comments at the screen. They danced in the aisles during the musical numbers. They threw rice at the wedding scene.
Mr. Piro’s love of the movie lasted the rest of his life. In the spring of 1977, he founded the “Rocky Horror Picture Show” Fan Club with several friends, who chose him as their president. He would ultimately see the film some 1,300 times.
He was still the club’s president — and the face of the “Rocky Horror” fan universe — when he died on Jan. 22 at his home in Manhattan. He was 72.
His sister, Lillias Piro, said the cause was an aneurysm in his esophagus.
Mr. Piro is credited with helping to turn the “Rocky Horror” mania that started at the Waverly into a broad phenomenon that spread to other theaters, in New York City and around the world.
He organized events with members of the film’s cast and sent out newsletters keeping fans up to date. He coordinated fans’ performances at theater showings, where he would head to the stage to introduce the film with a chant that began “Give me an ‘R’” and eventually spelled out “Rocky.”
“He was a very honest guy, you believed in him,” Lou Adler, a producer of the film, said in a phone interview. “He didn’t have ulterior motives. The fan club wasn’t a business or a means to something else, but to make it the very best for the fans, because he was one of them.”
In 2010, to celebrate the release of “Rocky Horror” on Blu-ray, Mr. Piro led a “Time Warp” dance with 8,239 participants in West Hollywood, Calif., which Guinness World Records certified as the largest such dance ever.
Salvatore Francis Martin Piro was born on June 29, 1950, in Jersey City, N.J. His father, Paul, was a construction worker, and his mother, Eileen, was a waitress.
Mr. Piro attended Seton Hall University from 1968 to 1972, the last two years at the university’s Immaculate Conception Seminary School of Theology, but he did not earn a degree.
He taught theology and directed plays at Roman Catholic high schools in New Jersey for three years before being laid off in June 1976. He spent that summer as the drama director of an all-girls camp before moving to Manhattan to pursue a career as an actor.
He waited tables and got some roles — and then came “Rocky Horror.”
Before it was a movie, “The Rocky Horror Show,” written by Richard O’Brien, had opened in 1973 as a stage musical in London. It became a smash hit there and had a brief run on Broadway two years later.
The film flopped in limited release in September 1975, but it was revived in early April 1976 as the midnight show at the Waverly.
And then came Mr. Piro, Mr. Shaiman and an expanding group of like-minded fans who became part of the early vanguard of audience participation. For Mr. Piro, talking back to the screen brought back memories of 1961, when he was 10 years old and watching “Snow White and the Three Stooges” at a theater.
“I remember that just as Snow White was about to bite into the poisonous apple, a voice from the theater warned audibly, ‘You’ll be sooorry!’” he wrote in “Creatures of the Night.”
Mr. Shaiman, the future Tony Award-winning composer and lyricist of “Hairspray,” said that he and Mr. Piro, friends from community theater in New Jersey, felt compelled to shout their comments at the screen once others began.
“Sal & I, both HUGE hams, knew we had to join in,” said Mr. Shaiman, who added that he had seen the film more than 70 times.
Mr. Piro, Mr. Shaiman and others in the small group who saw “Rocky Horror” early on will be the subject of a scripted movie, based on “Creatures of the Night,” to be filmed this summer.
“It’s hard to think of making the movie without him,” Adam Schroeder, one of the producers, said by phone.
Mr. Piro’s involvement in “Rocky Horror” was consuming, but it wasn’t a paying job. Over the years, he wrote greeting cards, a column for The Fire Island News, the three “Rocky Horror” books and the questions for a “Rocky Horror” trivia game.
He had a handful of film and TV roles — he played a “Rocky Horror” M.C. in a 1980 episode of the series “Fame” and a photographer in “The Rocky Horror Picture Show: Let’s Do the Time Warp Again” (2016), a made-for-TV remake of the original film.
From 1991 to 2014 he worked at the Grove Hotel, in the Cherry Grove community on Fire Island, first as the entertainment director of its Ice Palace nightclub and then as the manager of both the hotel and the nightclub. He also wrote and directed theatrical shows for the Arts Project of Cherry Grove.
In addition to his sister, he is survived by two brothers, James and Joseph.
Mr. Adler said that he saw Mr. Piro at a film event last month at IFC Center, as the Waverly, where “Rocky Horror” became a hit, is now known.
“He said to me we’re both reaching ages where something might happen to either one of us,” said Mr. Adler, who is 89. If that happened, he said Mr. Piro asked him, “Who’s going to watch over Rocky?”