In ancient times, before the phrases “global warming” and “peak oil” ruined our fun, Hollywood used to make car-chase comedies, automotive epics that were more about burnt rubber than good acting. An aspiring director like Ron Howard could launch his career with Eat My Dust and Grand Theft Auto. Burt Reynolds could slip on a hat and slip behind the wheel of a Trans Am and fans would follow Smokey and the Bandit anywhere.

That’s the tradition Hit and Run fits into. Hollywood gearhead Dax Shepard, of Baby Mama and TV’s Parenthood, rounded up his fiancée and When in Rome co-star Kristen Bell, and a bunch of their friends, piled into a collection of cars - classic and new - and tore up some California backroads in a movie about, well, tearing up rural California backroads.

Shepard plays “Charlie Bronson.” No, that’s not his real name. He’s in the witness protection program, far from Los Angeles. One thing that is real is Charlie’s love for community college “conflict resolution” teacher Annie (Bell).

“If you want, I’ll spend every moment with you for the rest of my life,” he coos to her in bed. She swoons.

That is tested when Annie has a shot at a job with a college in L.A. Charlie can kiss her goodbye and stay out of the city where his life is in danger. Or he can risk it all for love.

His accident-prone witness protection marshal (Tom Arnold) is against it. Annie’s ex (Michael Rosenbaum) is hell bent on stopping them.

And waiting in L.A. is the psychopathic, dreadlocked killer (Bradley Cooper, in fine form) just waiting for this guy not-really-named-Charles Bronson to make an appearance so they can settle old scores.

It’s a movie of random, comical cameos (Kristin Chenoweth, David Koechner) and raunchy riffs on senior citizen “swinger” clubs, prison sex and curing oneself of casual homophobic slurs. It doesn’t really hold together and stand up to much scrutiny. But the car stuff is fun, some bits are laugh-out-loud funny and Bell and Shepard make an adorable couple. When you see that yes, that’s really Shepard doing his own stunts and Bell is in the car with him, it adds to the movie’s retro sense of automotive anarchy.