After graduating from The Catholic University of America (studying acting and show business) in Washington, D.C. in 1957, Crowley headed west to Hollywood, where he worked for a number of television production companies before meeting Natalie Wood on the set of her film Splendor in the Grass.

[5] Wood hired him as her assistant, primarily to give him ample free time to work on his gay-themed play The Boys in the Band,[6][7] which opened off-Broadway on April 14, 1968 and enjoyed a run of 1,000 performances.

Crowley became part of Wood's inner circle of friends that she called "the nucleus", whose main requirement was that they pass a "kindness" test.

Off the success of the play, Crowley had a writing residency at Paramount Pictures, and wrote the screenplay for the movie Fade-In, which was directed by Jud Taylor and starred Barbara Loden and Burt Reynolds.

[10] In 2018 Boys in the Band was restaged on Broadway in a 50th anniversary revival featuring Matt Bomer, Jim Parsons, Zachary Quinto, and Andrew Rannells.