The New Leaf is about to turn over a new leaf. The 1971 black (romantic)comedy film, which starred Walter Matthau as a literal ladykiller and Elaine May as his wealthy prey, is being turned into a stage musical redubbed The Green Heart after the original short story by Jack Ritchie. Rusty Magee did the songs, and Charles Busch did the music, and Kenneth Elliott is staging a four-week workshop of the piece at Manhattan Theatre Club, starting June 24.

At its annual spring gala, MTC announced that The Green Heart would be the original musical it was promising in its mailings. Although the company does make a practice of premiering dramas, it also has a tradition of launching new musicals, dating back to the Tony-winning Ain't Misbehavin' and going to Putting It Together, the Sondheim songfest revue that starred Julie Andrews.

Karen Trott will star in the workshop as the would-be victim, Henrietta Lowell, and Patrick (Forbidden Broadway) Quinn will play her gold-digging never-lovin', Henry Graham. Other cast members include Mrs. Magee (Allison Fraser as Quinn's Germanic mistress) and two stalwarts from the last Guys and Dolls revival (Ruth Williamson and Ernie Sabella, playing as housekeeper and lawyer respectively). Fraser and Sabella are currently on Broadway in Tartuffe: Born Again and A Funny Thing Happened on the Way to the Forum.