Forty-one years after its premiere at the Ahmanson Theatre, Academy Award-winning writer Ernest Thompson (On Golden Pond) has deconstructed his script for The West Side Waltz. In the world premiere of Thompson’s newly revised, music and heart-filled comedy set during the tumultuous ’80s, Theatricum artistic director Ellen Geer; her sister, Melora Marshall; and daughter Willow Geer take on the roles of an aging concert pianist, her violin-playing spinster neighbor, and a would-be actress on New York’s Upper West Side. Will Geer’s Theatricum Botanicum, 1419 N. Topanga Canyon Blvd., Topanga, CA 90290 (midway between PCH and the 101/Ventura Freeway); $10-$42 (premium seats available for $60); The amphitheater is terraced into the hillside, so audience members are advised to dress casually (warmly for evenings) and bring cushions for bench seating. Patrons are welcome to arrive early and picnic before a performance. For a complete schedule of repertory performances, call (310) 455-3723 or go to www.theatricum.com.