As promised here last week, Motion City Soundtrack has a special show planned in its hometown following the completion of its fourth record: The quintet just announced a gig at the Triple Rock on Halloween Eve, Oct. 30 (4:30 p.m., all ages). Word is the show will involve costumes and other fun activities. Tickets ($12) go on sale Wednesday with a two-ticket limit per person. Look for the first single from the band's upcoming record, a track called "Disappear," to debut on iTunes tomorrow.