The concept is better than the execution of GroundUp Theatre's second round of cabaret-style songs and sketches based on real-life breakup letters. Uneven on opening night, the 45-minute show featured six ensemble members from a rotating group of nine. Todd Wojcik and Laura Coleman were the strongest performers I saw, bringing humor to an interpretive dance accompanying a sad letter/song and brazenly delivering a daring ode to sexual chemistry. Otherwise director Sabrina Lloyd's blocking is aimless, the transitions are abrupt, and the performances are just competent. Bringing these letters to life onstage is a good idea, allowing bitter audience members to laugh at the eccentricities of the brokenhearted. But with Valentine's Day approaching, be forewarned this is not a show for the romantic. There are lots of four-letter words, and the one used most often begins with F. Through 2/26: Wed and Sat 8 PM. Tue 2/8 and 2/22, 8 PM. Mon 2/14, 8 PM. Hungry Brain, 2319 W. Belmont, 773-218-3226. 21+. Free.