Richard Crouse

The last time Susan Sarandon went on a cinematic road trip she was teamed with Geena Davis in a film that reinvented the buddy picture and earned praise from critics who called it a “neo-feminist road movie.”

This time out the Sarandon shares the front seat with Melissa McCarthy. Where “Thelma & Louise” learned about loyalty and sisterhood, Tammy and Pearl only pick up tips about drinking and driving, how to rob restaurants and how to destroy a jet ski.

Tammy (McCarthy) is down on her luck. She hit a deer with her car—“Oh man,” she says, “not another one.”—got fired from Topper Jack’s, and discovered her husband (Nat Faxon) is having an affair with the neighbor (Toni Collette). And it’s not even dinnertime.

Like so many before her, Tammy decides to hit the road to clear her head. Trouble is, she doesn’t have a car or any money. Luckily Grandma Pearl (Sarandon) has both and is keen on taking a trip. “You’re not getting the car unless I go,” she says. “At this point you’re the best chance I have to get out of this house.”

The pair head off for Niagara Falls (going the wrong way naturally), stopping along the way just long enough to cause trouble as Pearl picks up a man in a bar (Gary Cole) before hiding out with Pearl’s cousin Lenore (Kathy Bates) and her girlfriend Suzanne (Sandra Oh). After a blow out with grandma at Lenore’s July fourth party Tammy finally has a close, hard look at her life.

Road movies are episodic by nature. Their stories move from place to place, from character to character, all bound by a theme. Unfortunately “Tammy” simply moves slowly from scene to scene, content to rely on McCarthy’s comedic appeal at the sacrifice of anything more than pratfalls and awkward humor.

In other words “Tammy” earns a laugh or two when McCarthy falls down, less so when she is standing upright, which is most of the movie.

McCarthy is a charming performer, but it’s beginning to feel like she doesn’t do anything than play the obnoxious loser with a heart of gold buried beneath a thick shell of one liners and non sequiturs. What worked so well in “Bridesmaids” now feels been-there-done-that.

She isn’t aided by the supporting cast, because despite the cumulative comedy cred of actors like Allison Janney, Dan Aykroyd and Toni Collette are all saddled with thankless roles that give them very little to do. Kathy Bates is more of a live wire, but shame on director Ben Falcone (who is also McCarthy’s husband and the film’s co-writer) for not giving her costar Sandra Oh more to do. She is essentially set dressing, a flesh prop with a nice wardrobe.

By the end of the credits “Tammy” doesn’t feel like a comedy—although there are several giggles sprinkled throughout—as much as it does a waste of talent. Sarandon isn’t a gifted comedian but McCarthy is, but neither is working to their strengths.