When in doubt, goof on the ’70s. That’s the lesson of the big-screen version of Starsky & Hutch, where the laughs come from Ben Stiller and Owen Wilson parodying the polyester excesses of the disco decade. Bits from the show get regurgitated in the Stiller-Wilson revamp: Hutch’s wealthy-cowboy disguise is a tip of the hat to episode 12. (Starsky alter ego Maury Finkle, by contrast, is all Stiller and pure genius.) The film sustains a genial mockery that extends to the extras: In the droll on-set documentary, everyone in the cast expresses intense loathing for everyone else. Even Soul and Glaser, poker-faced as ever, drop by to dump on the proceedings.