Kate Upton and Cameron Diaz star in 'The Other Woman,' in which every gag is milked dry

I laughed a few times while watching the slapstick sisterhood comedy “The Other Woman,” but most of the time I was grim-faced. You can’t complain that the filmmakers – director Nick Cassavetes and screenwriter Melissa K. Stack – aren’t enthusiastic about their hijinks. Practically every gag in this movie, and there are scores of them, is milked dry. When the gags aren’t very good to begin to with, this is a prescription for disaster.

Cameron Diaz plays a tough-cookie attorney who discovers her dreamboat boyfriend (Nikolaj Coster-Waldau) is a married man. The crumbum’s wife, played in full screech by Leslie Mann, is a homebody who, wronged, discovers her inner avenger. She’s still sweet, though. Harmlessness, after all, is this movie’s calling card.

Tastefulness, not so much. In keeping with the “Bridesmaids” tradition, not to mention the standard-issue slobbola guy comedies, bathroom breaks are occasions for gross-outs.

Kate Upton plays the third in a trio of ladies ganging up on the philanderer, and it’s a good thing she has a career as a supermodel. Grade: C- (Rated PG-13 on appeal for mature thematic material, sexual references and language.)