"Write what you know" is a piece of advice that many writers follow, so it should come as no surprise that Mart Crowley, the writer behind The Boys in the Band, drew inspiration from his own friend group.

He admits that he based the lead character, Michael (Jim Parsons), on himself, and Harold (Zachary Quinto), Michael's closest frenemy, was inspired by his best friend, Howard Jeffrey, who has an interesting history himself outside of running late for birthday parties.

In a new behind-the-scenes video, Crowley reminisces about his friendship with Jeffrey, who was a popular choreographer and dancer in Hollywood. Jeffrey taught Natalie Wood her dances for West Side Story, and he was also trusted by Barbra Streisand, who requested that Jeffrey dance with her onscreen in the Ziegfeld Follies musical number from Funny Girl. He later reunited with Streisand for Hello, Dolly! and On a Clear Day You Can See Forever.

Unfortunately, like many gay men of his generation, Jeffrey died of complications from AIDS in 1988 at the age of 53.

"Howard was as he is in the play: the truth-teller, the demolisher of all pretention," says Crowley in the video, adding that Jeffrey was his best friend. "Howard could always read me that way and not let me get away with anything."

As NewNowNext previously reported, Crowley died on March 7, 2020, at the age of 84 from complications related to heart surgery.

“The significance of The Boys in the Band cannot be underestimated,” said producer Ryan Murphy in a statement when the Broadway run was announced. “In 1968, Mart Crowley made theatrical history by giving voice to gay men onstage, in this uncompromising, blisteringly honest and wickedly funny play.”

Below, watch the exclusive video of Crowley, Quinto, and director Joe Mantello discussing Jeffrey and how he inspired the character of Harold.

The Boys in the Band hits Netflix on September 30.