EXCLUSIVE: In Cahoots shingle has teamed with writer/producer Joy Gregory to develop a feature adaptation of the off-Broadway musical The Shaggs: Philosophy Of The World. The musical is based on the real-life story of a trio of sisters whose late-’60s band polarized critics. They were dubbed visionary by some, while others called them the worst band in rock history, whose sound was reminiscent of cats being strangled. Gregory wrote the book for The Shaggs, with music and lyrics by Gunnar Madsen and the band itself. The musical recently played off-Broadway at Playwrights Horizons, where it was nominated this past year for a Lucille Lortel Award and a Drama Desk Award.

Gregory and In Cahoots partner Alexandra Beattie will produce. Gregory is writing the script. Beattie and Gregory secured the band’s life rights from the two surviving members, Betty and Dorthy Wiggin, who’ll be consultants on the picture.

The Shaggs were teenage sisters from rural New Hampshire who formed a band in 1968 at the insistence of their overbearing father, who was convinced their talent would make them stars. Their lone studio album, Philosophy Of The World, was ridiculed and barely released, but it was rediscovered in the early 1980s and hailed as groundbreaking outsider music by the likes of Kurt Cobain and Frank Zappa. Rolling Stone’s Alt-Rock-A-Rama in 1996 ranked it among the 100 most influential alternative LPs ever released, and in 2007 Blender Magazine named it the 100th most important indie rock album of all time.

Gregory was first approached in 2003 after the first production of the musical in Los Angeles. “Most people are startled when they hear The Shaggs for the first time,” a producer said. “Their sound is awkward and unpolished, but their songs have a purity of expression that no amount of musical training can give you. And behind the music is a powerful story of three girls who yearn to rise above their meager existence, while under the yoke of demanding father who believes they are destined for greatness.”

Gregory, who is co-exec producer of the ABC Family series Switched At Birth, has written and produced such series as Felicity and Joan Of Arcadia. She wrote the Shaggs story after becoming a devotee of the band and its one album, which she discovered in the late ’90s. Between the LA and NYC productions, she further developed the musical at the Lookingglass Theatre Company in Chicago, of which she’s a co-founder. “I always saw the potential of this story to be a compelling indie film, in the same outsider spirit the Shaggs pioneered in the late ’60s,” she said. “I tried to capture that offbeat tone in the play, and I look forward to bringing it to a broader audience onscreen.”

Beattie is represented by UTA and Code Entertainment. Gregory is represented by ICM and Schachter Entertainment.