With their successful blend of improvised comedy and song continuing to entertain the semi-masses on a weekly basis, the Secret Improv Society’s popular theatrical shows are not so clandestine anymore. A bunch of San Francisco’s best improvisers, comedians and musicians often come out to play with the sharp-witted regular cast, too. It all results in a fast-paced, high-energy revue, featuring plenty of audience input and interaction. Volunteers can even join the fun onstage. No two shows are ever identical, so repeat visits are strongly suggested.