The presence of the mob in Chicago has flagged since the days of Al Capone and Bugs Moran, but the group-work spirit is alive and well. After drummer Scott Plouf left Portland’s Spinanes to join Built to Spill, singer and guitarist Rebecca Gates took off for the Midwestern mecca and joined forces with the city’s indie elite for 1998’s Arches and Aisles. Gates has since shed the Spinanes name, but she still gets by with a little help from her friends. Her solo debut, 2001’s Ruby Series, features John McEntire of Tortoise and the Sea and Cake, Brian Deck of Califone, and Noel Kupersmith of Brokeback. The sound is mellow and loungey—the disc was co-produced by McEntire with a somewhat heavy hand, with a few tracks sounding suspiciously like the Sea and Cake—and marks a departure from Gates’ Spinanes-style guitar. But that record is over 2 years old, so see what Gates has been cooking up in the meantime when she plays with Chris Brokaw at 9 p.m. on the Black Cat’s Backstage, 1811 14th St. NW. $7. (202) 667-7960. (Anne Marson)