Beginning with a breathless sprint through the history of gay male erotica, Porn Star then introduces us to four current stars of the genre — Brent, Colby, Johnny, and Rocco (who’d a-guessed they were porn stars with names like those?) — who straddle the gay/straight line with surprising aplomb. This is interesting up to a point, as are some of the doc’s insights into the mechanics of the porn biz, but each guy seems to tell the same story at least twice. Sun. Oct. 6, 10:15 p.m., Tampa Theatre.