NEW YORK -- In a room in a lower Manhattan skyscraper, a musical is being born, song by song.
Standing at a piano is an up-and-coming songwriting team, presenting a new tune called "Think of Cheese" from its fledgling show "Afterland," which takes place outside post-apocalyptic Philadelphia. Composer and co-lyricist Benjamin Velez launches into a flamenco-flavored ditty.
"See the cheese, see the cheese/See the Parmesan is snowing/On the trees/Ooh, la-la/Smell that pungent odor blowing," sings Velez, as his co-writer Kathryn Hathaway looks on, somewhat nervously.
Some two dozen fellow lyricists, playwrights and composers fill the seats, all hoping to join the list of musical heavyweights who have gone through this classroom process, including Alan Menken, Lynn Ahrens, Steve Flaherty, Maury Yeston, Tom Kitt, Brian Yorkey and Amanda Green.
The song over, it's time for the young composers to face the music.
Hands go up in the class. One student complements the team on a song with spectacular music and clever lyrics but wonders who is making cheese in post-apocalyptic Philadelphia. Another wonders to whom exactly the song is being sung. Someone else wants to know what the song's function is in the show. Still another hates the title.
Velez and Hathaway graciously take the criticism and sit down. There are five more songs to be presented on this day, including a tune about a 12-year-old science-obsessed girl in the 1950s trying to be cool, and a song sung by a woman who has found foot-fetish porn on her husband's computer.
This class is part of the BMI Lehman Engel Musical Theatre Workshop, and judging by its track record as a top-notch incubator of musicals, there's a good chance that in a few years there will be a new Broadway show with a song about post-apocalyptic cheese.
"It gives writers something that is very hard to come by: an audience every week," says "The Book of Mormon" co-writer Bobby Lopez, who for the last three years has helped moderate the advanced group with his wife, composer Kristen Anderson-Lopez, whom he met at the workshop.
Shows nurtured by the program include "A Chorus Line," "Little Shop of Horrors," "Nine," "Once On This Island," "Ragtime," "Avenue Q" and "Next To Normal." Six musicals currently playing on Broadway were authored or co-authored by members of the BMI Workshop: "Aladdin," "Newsies," "The Book of Mormon," "Violet," "If/Then" and "Rocky."
"We don't tell people what to write or how to write or even what style to write in. But we do teach and talk a lot about how musicals are put together," says writer and lyricist Patrick Cook, the program's director, who is a former workshop student.
"We're one of the only places that actually talks about the craft of musical theater and how it's a different craft than almost every other art form," he adds.
The BMI workshops started in 1961 and its three-year program goes from learning the basics of songwriting to the creation of full-length musicals. Seasoned veterans attend the advanced workshop to present ongoing projects. New songs from a fresh batch of composers will be presented Thursday at a showcase at the BMI's home at 7 World Trade Center.
One early assignment is to write a song that is either a sad hello or a happy goodbye, which both turn out to be devilishly hard. "It forces people to write with some kind of subtext," says Cook.
Cook should know: He first joined the workshop as a student in 1984. "I thought I knew everything. And after the first class, I went, 'Oh, I don't know very much, do I?'" he says, laughing.
Anderson-Lopez, who won an Oscar with her husband for the music to the smash film "Frozen," says she owes a lot to the workshop. "For me, it was one-stop shopping for a life," she says.
She was pursuing a ho-hum career as a musical theater actress -- "I was playing a lot of nuns in New Hampshire" -- but doing a lot of rewriting of lyrics on the side. She couldn't afford a master's program but someone suggested the BMI, which is free to participants.
"Within a month, I had realized: 'I am a writer. This is what I need to do.' The sky opened up and a hand reached down and said, 'Follow this path.' And then I met my future husband," she says. "My life fell in place."
Robert Lopez, who also met his "Avenue Q" songwriting partner Jeff Marx at the workshop, says feedback from fellow writers is invaluable, particularly if they help identify recurring problems.
"You're trying to help the person write the show they want to write -- not the show you would write and not steer them away from something that's not your cup of tea," he says. "You're trying to help them do what they want to do."
Sometimes the results are good, sometimes poor. Sometimes, though, they are sublime. Cook recalls being at a workshop in which Lopez and Marx presented the song "If You Were Gay" from what would become "Avenue Q."
"There is nothing like the magic when something is working. It's what I live for. It's what a lot of the writers live for," he says. "All of a sudden, there's going to be a song that stops the room dead and you can hear a pin drop. There's going to be a moment of theater magic in that room."