Nick Cassavetesí comedy The Other Woman is loaded with likable performances, but the script by first-time screenwriter Melissa Stack adheres so slavishly to conventional Hollywood wisdom that the movie never feels as fun as it should. Venture capitalist Mark (Nikolaj Coster-Waldau) is a lying, conniving sociopath, something his wife Kate (Leslie Mann) and his mistress Carly (Cameron Diaz) discover when Carly ñ who had no idea her boyfriend was married -- tries to surprise Mark at his home. The two women have polar-opposite personalities -- Kate is a little ditzy and very insecure, while Carly is a confident, high-powered lawyer -- but they soon begin to talk and bond. Kate eventually decides that she wants revenge, so she and Carly cook up a plan to ruin Markís life. They find allies in Kateís brother Phil (Taylor Kinney), and, unexpectedly, Markís other mistress Amber (swimsuit model Kate Upton). Director Nick Cassavetes has jumped back and forth between indie fare (Sheís So Lovely, Yellow) and more mainstream material (John Q, My Sisterís Keeper), and the best aspect of his work has consistently been his rapport with actors. He always draws good -- and sometimes great -- performances from his cast, and while thereís nothing great overall about The Other Woman, you definitely donít mind spending some time with its characters. Unsurprisingly, Leslie Mann gets most of the laughs. She has a knack for twisting a line reading in a way that keeps the audience off-kilter -- somebody should cast her and Lisa Kudrow in something as soon as possible. Diaz lets herself look her age, and, as when she played the super-mousy wife in Being John Malkovich, letting go of physical perfection allows her to seem more real. Sheís loose as she plays the straight woman to Mannís motormouthed extrovert. The biggest surprise is Kate Upton, who is pretty good as the young hottie Mark starts sleeping with after his wife and mistress stop having sex with him. On paper she seems like stunt casting, and that she wouldnít need to provide anything other than a perfect body and a pretty face, but she doesnít force anything and scores some laughs with the dumb-blonde schtick written for her. Additionally, Don Johnson gets to have fun as Carlyís benignly lecherous father. That dumbness, unfortunately, plagues the whole script. Both Amber and Kate vacillate between stupid and savvy depending on what best suits the story and the comedy. This lack of consistency makes it difficult to invest in the characters emotionally, although when the movie steals the laxative/bathroom scene from Dumb and Dumber, it is fair to say that character development is hardly the point. Thereís a great film to be made from the idea at the core of this story, but The Other Woman never gets near it. The characters may drink whisky, tequila, and gin, but the movie itself is white wine -- the likely drink of choice for its target demographic.