Although Melissa McCarthy became a TV star and an Emmy winner by playing the sweethearted, straight-laced center surrounded by wackos on the sitcom Mike & Molly, her television character is 180 degrees different from her film persona, which has followed the template of her physically expansive, filter-free breakout part in Bridesmaids. She's more or less gone back to that well in her subsequent hit movies -- Identity Thief and The Heat -- and now again with Tammy. She co-wrote the script with the film's director (and her husband) Ben Falcone, and all evidence suggests she's in the "if it ain't broke, don't fix it" phase of her career.
McCarthy stars as the title character, a none-too-bright (she doesn't even know who Mark Twain was) fast-food employee from Illinois who, in the opening minutes of the movie, loses her job, her husband (Nat Faxon), and her car. In order to shake up her life, she agrees to go on a road trip with her alcoholic and diabetic grandmother Pearl (Susan Sarandon) to see Niagara Falls, despite the objections of her well-meaning mother (Allison Janney). As the twosome make their way across the Midwest, Tammy learns a few lessons about growing up, old family secrets are revealed, and the overweight protagonist falls down a bunch.
This being a road-trip movie, the duo meet up with a number of outlandish characters along the way; these include Earl (Gary Cole), a horny farmer who takes a liking to Pearl, and Earl's decent son Bobby (Mark Duplass), who provides Tammy with the possibility of new love. There's also Pearl's wealthy lesbian cousin Lenore (Kathy Bates) and Lenore's significant other Susanne (Sandra Oh), who lend a hand after Tammy robs a fast-food place in order to get the money to spring her soused grandmother from jail.
Tammy was co-produced by Will Ferrell and Adam McKay, and had it come out pre-Bridesmaids, odds are good it would have done for McCarthy what another Ferrell/McKay flick, The Foot Fist Way, did for that movie's co-writer and star Danny McBride: establish her obnoxious onscreen personality and give her the break that would have led to bigger and better things. However, she's already a bona fide box-office queen. Audiences don't need to be introduced to her; they need to see what else she can do, and Mike & Molly is proof that she is capable of so much more than being a bull in a china shop.
Tammy offers nothing new whatsoever for McCarthy's fans, and that's undoubtedly intentional. It's distressing that she had a hand in writing and producing this movie, only to return to a bumbling comic type that she's close to exhausting. Only when she's paired with really strong actors -- especially Kathy Bates -- does McCarthy make her character seem like a real person and not just a comedic construct. She's a talented actress, but Tammy is the work of a star temporarily bereft of inspiration or ambition.