Can you plan an anniversary party without a plan? Unexpected Productions, the longtime Seattle improv troupe, is out to do just that this weekend: The company is celebrating its 30th anniversary with a 30-hour “improvathon.” The entire weekend-long show will be created from audience suggestions, in keeping with Unexpected Productions tradition. (Organizers warn the fidgety that there will be a 5-minute break every hour.)

Audience members who make it through all 30 hours will receive a lifetime pass to see any of the company’s shows.

First show is 6 p.m. Friday. Last show begins at 10:30 p.m. Saturday and ends at midnight, at 1428 Post Alley, Seattle; each performance is $15; a pass is $20, allowing you to come and go as you please, or hang on for the whole improvathon. More info: 206-587-2414 or www.unexpectedprodutions.org.

Seattle Times staff