What would happen if that historic hotbed of avant-garde activity, the Ontological Theater at St. Mark's Church, invited back a whole slew of its artists dating from 1993, when it first opened its doors to outside, emerging theater groups? We'll find out in October, when the theater hosts SINTESI/dogpile, a rapid-fire, 5 minutes-a-pop mini festival for Ontological artists of past and present (and maybe some future). Every night is a different line-up, with Travis Just DJing after the performances. Emily and Ian and Judith's play has it's first and last performance on THURSDAY, OCTOBER 2: 8 p.m. Tickets $17 adults/$12 Students Purchase in advance here or by calling 212-352-3101 Cash only at the door. Ontological Theater at St. Mark's Church 131 East 10th Street (at 2nd Avenue) THAT NIGHT FEATURES 5-MINUTE PERFORMANCES BY: Target Margin Object Collection Cherry Red Productions (THAT'S OUR PLAY!) Jake Hooker and Noel Allain Old Kent Road Theater Anthony Cerrato NY Neo Futurists Jonathan Marmor Paula Matthusen Bone Orchard/Anna Jones Tiny Elephant