From left, Rod Cachola, Jordan Savusa and Garrick Paikai — with guest improvisers Troy Apostol, K.C. Odell and Shannon Winpenny — bring "On the Spot: Behind the Door" to The ARTS at Marks Garage, 8 p.m. today.

The guest improvisers are challenged to figure out their roles in the middle of a scene. This format is based on the Australian TV show "Thank God You're Here."

Tickets are $14 general, $10 students; available an hour before showtime. 550-8457, www.honoluluboxoffice.com.