NEW YORK (AP) — At age 9, America Ferrera came across a videotape that changed her life.
It was the 1993 TV movie of the musical "Gypsy" starring Bette Midler with music by Jule Styne and lyrics by Stephen Sondheim.
"I probably played that VHS 500 times. Maybe more. I learned every lyric, every breath, every pause," the "Ugly Betty" and "The Good Wife" actress says. "It was then that I decided what I wanted to be when I grew up — I wanted to be Bette Midler."
Alas, that was not to be, but imagine Ferrera's surprise when she got an offer to audition for a singing part in a new documentary about Sondheim, whose landmark musicals include "West Side Story," ''Company" and "Sweeney Todd."
"My first thought was, 'Never! I will never go in and sing for Stephen Sondheim. That sounds like a nightmare.' And then I thought, 'You know, if I'm going to be rejected by anyone in musical theater, it should be by Stephen Sondheim.'"
Ferrera won the part, and listening to her sing is a highlight of the intriguing documentary "Six by Sondheim," which airs Monday on HBO (9 p.m. Eastern).
Directed by longtime Sondheim collaborator James Lapine, the film uses dozens of TV interviews of the revolutionary composer spanning 50 years to tell his story through six of his songs.
"We didn't really any of us want to do a very conventional autobiographical documentary on him, so this is what we hit upon," says Lapine. "I think the idea from the get-go was to try and see if we (could) make a movie with him being the only one who speaks."
The interviews are mostly appearances on TV chat shows over the years augmented by some 20 hours of conversation that Lapine recorded three years ago for Sondheim's 80th birthday.
The six songs featured — "Something's Coming," ''Opening Doors," ''Send in the Clowns," ''I'm Still Here," ''Being Alive" and "Sunday" — are presented either as archival recordings or new performances.
That's where Ferrera came in. She teamed up with Jeremy Jordan and Darren Criss to perform "Opening Doors," a touching song from "Merrily We Roll Along" about three young artists hoping for their big breaks.
One other distinguished person helped them out: Stephen Sondheim. That's right, the master himself sang the part of a skeptical musical theater producer. ("There's not a tune you can hum," he grouses in it.)
Jordan, a rising star who has appeared on TV in "Smash" and on Broadway in "Newsies," met Sondheim for the first time during the three-day shoot seven months ago and calls him "brilliant."
"It was pretty fast and furious," says Jordan. "It was over before it had even begun so I don't think I fully grasped the enormity of it while we were doing it, which is good because then I probably wouldn't be able to perform as well."
How did Lapine persuade Sondheim to sing a song he wrote? He just called up his old friend and collaborator and asked. "I think there was an enormous pause at the other end of the line and he finally said, 'OK,'" says Lapine. "He was so trusting."
Other performers who sing in the documentary include Audra McDonald, Jackie Hoffman, Laura Osnes and Jarvis Cocker. "I feel I was lucky enough to be just inside the Sondheim loop to be asked to be a part of it," says Osnes, who stars in "Rodgers + Hammerstein's Cinderella."
Viewers may learn some intimate details about Sondheim: He likes to compose lying down and sometimes enjoys a cocktail to loosen up as he writes. His rough, solitary childhood is also explored, including a shocking letter he received from his mother telling him that she regretted giving birth to him.
While some personal details make Sondheim blush, he says they lead to a fuller understanding. "You don't want to just have baby pictures of yourself and how cute you are," he says. "You have to show who you are."
One thing Sondheim noticed while watching interviews of himself over the years is his image as an angry man in the 1970s, his hair long and his resentment on full show.
"I'd forgotten how sour I was," Sondheim says with a laugh. "I truly had forgotten that period of my life where I was really down on everything. So that was interesting to see."
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