'Hit and Run' fires on all cylinders

Sharp comic timing and perfect chemistry between lead couple (and real-life fiances) Kristen Bell, right, and Dax Shepard boosts the enjoyable rom-com 'Hit and Run.' (Credit: Jerry Reed, Open Road Films)

Like the muscle cars it lovingly features, Hit and Run (* * * stars out of four, R, opens Wednesday) idles effectively, revs and takes off with frisky energy, and knows just when to cruise.

A romantic comedy in which the lead couple has sharp comic timing and radiates chemistry, it's also peppered with car chases and controlled chaos. This fun-loving genre-bender, inspired by Smokey and the Bandit, opens languidly, then picks up the pace. Even in the midst of cars racing, it's funny and endearing.

Co-director, writer, editor and star Dax Shepard plays Charlie Bronson, and his real-life fiancée Kristen Bell is his girlfriend Annie, a professor with a doctorate in non-violent conflict resolution. She's happily in love with Charlie, who dotes on her. He's in the witness protection program and spends his days hiding out in the house they share in a sleepy central California town.

Everything is fine in their lives, which are enlivened by the intrusions of Randy (Tom Arnold), the accident-prone U.S. Marshal in charge of Charlie's case. His transportation mishaps grow repetitive, but his use of a fictional iPhone app is pretty hilarious.

Annie is offered a chance to head up a new department at a university in Los Angeles and, in a matter of hours, their lives go from quietly predictable to precariously dangerous. Charlie knows Annie shouldn't pass up this opportunity, but he's not supposed to return to Los Angeles, the scene of his crime.

Suddenly, they're running for their lives. Along the way, she learns his real name and that he drove the getaway car in a bank robbery. Hot on their trail is Charlie's former partner-in-crime Alex (Bradley Cooper, nearly unrecognizable in dorky shades and dreadlocks) and Alex's accomplice girlfriend Neve (Joy Bryant).

The movie's best moments are the funny-sweet exchanges between Shepard and Bell and the ridiculous banter between Cooper and Shepard.

Because Annie believes in resolving conflict peaceably, she makes Charlie promise not to resort to violence as they flee their pursuers. What comes of that promise and their discussions on the issue are equal parts earnest and comical.

The action-packed rom-com hinges on the likability of the low-key Shepard and the bubbly Bell, and their connection has a fresh, winning charm.

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