Here’s something I never thought I’d say: An actor from “Punk’d” has made one of the most entertaining movies of the summer. And here’s something else — the film is uproariously funny without relying on the kind of juvenile pranks you might expect.

We’ve been underestimating Dax Shepard. But he can’t really blame us. The girlfriend of his character in the movie — played by his real-life fiancee — does, too. “I’m not going to teach conflict resolution and then marry Dog the Bounty Hunter,” she tells him once, with exasperation. Only those involved know just how autobiographical the characters and relationships of “Hit & Run” are. But there seems something very real about this story of a smart, classy young woman struggling with her love for a guy who likes to build loud cars– minus the stuff about being on the run from a criminal gang, that is.