NEW YORK — Before “Mandy” and multiplatinum albums, Barry Manilow and his longtime collaborator Bruce Sussman wanted to write for the musical stage.
“Bruce and I have been trying to write musicals from the very, very beginning — back when we met in 1824,” said Manilow, a youthful and playful 80, overstating his age by about a century and a half.
But instead of bursting onto Broadway, the two New Yorkers found their calling in pop music.
Fans flocked to Manilow’s capacious catalog of catchy tunes — many, including his signature “Copacabana (At the Copa),” leavened by Sussman’s lyrics. Manilow’s early career jingles, including one for State Farm, endured through the years. The pair even wrote animated films.
At the same time, for decades, the king of Billboard’s adult contemporary charts and the inventive Sussman struggled to crack the musical theater code.
That ends Monday.
“Harmony” is due to open on Broadway at the Ethel Barrymore Theatre, more than 25 years after an excited Sussman, emerging from a three-hour historical documentary, called Manilow from a rain-soaked pay phone on Lafayette St. in Manhattan with a concept for a musical.
The emotional show tells the true story of the Comedian Harmonists, a group of six singers — three of them Jewish — who climbed to the top of the German entertainment world before the Nazis crushed them and thrust their music into the dustbin of history.
The morose story mixed with Manilow’s characteristic earworm melodies leaves audiences humming at times, and tearing up at others.
“People should know that they should bring tissues,” said Julie Benko, who plays a feisty Jewish activist who falls in love with a member of the group. Her fraying relationship with her beloved offers one of the show’s most poignant, bittersweet moments.
It is not all gloomy. There is the funny, frothy, Sondheim-esque “Your Son Is Becoming a Singer,” with lively orchestrations and lyrics such as: “I know you will find it ironical/a smear on the family chronicle/oh, Daddy hold onto your monocle.”
Another slapstick number puts the whole band in their underwear. In one song, the band, dressed as clownish puppets, mocks the Nazis. A song at the start of the second act evokes “Copa.”
Manilow said pop music is largely limited to two tones: “‘I love you,’ or ‘I miss you.’”
“If you come up with a good idea, they usually say, ‘Well, that would belong to a Broadway musical,’” he said. “Of course, you can do anything you want with Broadway.”
Manilow and Sussman, who are both Jewish, embraced the flexibility of the form. Sussman wrote the book and the lyrics. He joked that his first draft, completed in the mid-1990s, ran about 700 pages long.
Over the years, and through scattered smaller-scale productions, the musical has been trimmed down to size.
Before a soldout run at New York’s National Yiddish Theatre Folksbiene last year, a new character was introduced: an older version of one of the singers, who is a rabbi and serves as the musical’s narrator.
The new narrator, the band’s last surviving member, is played with endearing warmth by Chip Zien, a Broadway veteran who commands the stage and anchors the show.
Zien, initially hesitant to take the role, said that when he read the script, he was “floored” by the beauty of the story. But he could not picture what the score would sound like. Manilow got to work.
The songwriter recorded the older rabbi character’s entire part and sent the audio to the actor, Zien recalled.
“I have Barry Manilow on my cellphone singing every single thing I sing in the show,” Zien said. “And I have a lot to do.”
