We've heard them as a deliriously cranky, Fall-like outfit, which is to say just off-kilter enough to entice. On their myspace.com page, where you can hear four songs, they file themselves under the "Mexican/Rock/Progressive" slot. Hmmm. Ask Nudelman today and he describes The In Out's music as "post-millenial web surfer minimalism." They're at the Plough & Stars Saturday Oct. 4. They're on at 10, followed by the Dirty Truckers an hour later. Cover: $5.

912 Massachusetts Ave., Cambridge, 617-576-0032 www.ploungandstars.com