Screenwriters on Broadway

Norbert Leo Butz, Zachary Unger and Sarrah Strimel in "Big Fish" at the Neil Simon Theatre in New York. (Paul Kolnik / The Hartman Group via Getty Images / September 4, 2013)

NEW YORK — Recently, writer John August watched a DVD of "Big Fish," the 2003 film directed by Tim Burton for which he wrote the screenplay.

He says it was an enjoyable but odd experience.

"I kept wondering, 'Why aren't they singing?'" recalls the 43-year-old screenwriter with bemusement. He has been working on adapting the material for the musical stage for the past nine years — four more than it took him to write the film.

There are now songs — plenty of them — in August's book for "Big Fish," a collaboration with composer Andrew Lippa and director-choreographer Susan Stroman that opens Sunday on Broadway.

One of the most highly anticipated musicals of the season, the $14-million "Big Fish" is one of the many stage musicals hoping to extend the life of the movies on which they are based.

PHOTOS: Arts and culture in pictures by The Times

If the producers are willing, some of the films' writers try to make the transition — August, Woody Allen with "Bullets Over Broadway," Andrew Bergman with "Honeymoon in Vegas" — and some do not. Veteran librettist Tom Meehan is adapting "Rocky," for example, not Sylvester Stallone. Marsha Norman has adapted "The Bridges of Madison County," not Richard LaGravenese.

And as more and more films are becoming Broadway source material, the graveyard is littered with musicals in which screenwriters have proved incapable of separating themselves from their original scripts to meet the demands of the stage.

Although the book is often blamed for an unsuccessful show, whether it's by a

screenwriter or not, such high-profile failures as "9 to 5" and "Ghost" call attention to pitfalls for a theater outsider who created it for a different medium.

A number of Broadway-bound musicals adapted by their respective original writers have run into development trouble. After postponing its announced Toronto tryout last year, Bergman's "Honeymoon in Vegas" is in its world premiere engagement at the Paper Mill Playhouse in New Jersey. Barry Levinson's adaptation of "Diner," with music by Sheryl Crow, appears to be in limbo after numerous postponements.

PHOTOS: Hollywood stars on stage

"The temptation is to be very literal to what you did before because that's what worked," August says. He didn't watch the movie or refer to the script while he was working on the musical.

"I didn't want the choices to be made for the wrong reasons. The right choice was to look for those moments that could be transcendent because they were onstage, not because they could be translated from film," August says.

"Big Fish," based on a novel by Daniel Wallace, is a bittersweet family drama about Edward Bloom, a blustery Southern fabulist who spins heroic tales of encounters with a witch, a mermaid, a giant, a werewolf, and assorted freaks and evildoers.

At first, these fantastical stories enchant his son, Will, but eventually he becomes estranged. Sandra, the mother and wife, tries to help bridge the gulf between father and son when Edward is diagnosed with a terminal illness.

August remembers a test screening of the film in Orange County in 2003, when he approached the producers Bruce Cohen and Dan Jinks and told them the characters "sang" to him. "I think we should try to turn this into musical, but I don't know where to start," August says.

That was not entirely the case. He'd written "Corpse Bride," an animated musical, and "Charlie and the Chocolate Factory" for Burton. Even in the film of "Big Fish," he'd written lyrics for a Danny Elfman tune, "Twice the Love," sung by the Siamese twins Ping and Jing.

But August had never before written a musical for the stage. "I had a pretty good sense of the vocabulary for it but had not been steeped in it," he says.

Cohen and Jinks, who won the Oscar for "American Beauty" and are lead producers on the musical, put August together with composer Andrew Lippa ("The Wild Party," "The Addams Family"). For the first five years, the two hashed out the parameters of the musical, throwing out scenes and characters from the film without hesitation.