CHECKMATE

Victor Cahn’s new suspense thriller “Fit to Kill” follows a charming chess master married to a rich older woman. Through Saturday, 8 p.m., Harold Clurman Theatre, 410 W. 42nd St., between Ninth and Tenth avenues, 212-279-4200, $15.

PHYSICS COMEDY

“Happy Hour at the Event Horizon” mixes science, cocktails, and comedy to create a performance billed as “the weirdest show you’ll see this year.” Albert Einstein and Niels Bohr relax at a bar on the edge of a black hole, chatting with an escaped photon, an elderly galaxy, and a riotous gang of theories. Through Sunday, tomorrow-Friday, 8 p.m., Saturday, 3 and 8 p.m., Sunday, 3 p.m., Blue Heron Arts Center, studio theater, 123 E. 24th St., between Park Avenue South and Lexington Avenue, 212-868-4444, $12.

TIME MANAGEMENT

In Jessica Bowser’s new experimental play “It’s About Time,” a depressed young man submits to a strictly regimented self-help program. The show, which uses music, video, and theater, is currently in previews. Adam Bernstein directs the Confluence Theatre Company production. Opens: Thursday, 8 p.m. Through Saturday, May 14, Thursday-Saturday, 8 p.m., Chocolate Factory Theater, 5-39 49th Avenue, Long Island City, Queens, 718-482-7069, $15. Note: An additional performance takes place tomorrow at 8 p.m.

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