Review: 'The Secret Life of Walter Mitty'

(CNN) -- It's easy to understand why comedians like Jim Carrey, Mike Myers, and Sacha Baron Cohen have flirted with adapting James Thurber's 1939 New Yorker story about a timid man with a vibrant fantasy life. Not only has CGI made it relatively simple to turn Walter Mitty's daydreams into Technicolor tapestries of digital eye candy, it's also the kind of emotionally textured role that can be a springboard out of the banana-peel slapstick ghetto. Ben Stiller's no stranger to such clown-crying-on-the-inside gambits (see: "Permanent Midnight" and "Greenberg"). But his new film, "The Secret Life of Walter Mitty," despite all of its visual razzle-dazzle, never locates the beating heart of its hero.

Stiller, who also directed, plays Mitty as an absentminded, socially awkward nebbish who works in the photo department at LIFE magazine. The irony, of course, is that even though he works at a place called LIFE, he hasn't lived. Instead, he retreats into his head and imagines himself a dashing mountain climber or a hot-blooded Casanova. Stiller and screenwriter Steven Conrad have given Thurber's story a 21st-century twist by setting the film in our era of corporate downsizing. LIFE is about to cease publishing, and for its final cover the editors have chosen a shot from their globe-trotting photojournalist star, Sean O'Connell (Sean Penn). Then Mitty misplaces the negative. And with the encouragement of a co-worker he's sweet on (Kristen Wiig), he embarks on a quest to find O'Connell, leading him to Greenland and the Himalayas.

As Stiller's Mitty crisscrosses the planet, he slowly transforms into the action hero he's always been in his fantasies. While stunning sequences show him skate-boarding away from an erupting volcano and fighting off a great white shark, the character never becomes more than a fuzzy conceit. At the risk of psycho-analyzing a film that's already too deep inside its own head, Stiller seems to lack the confidence as a dramatic actor to fully commit to the emotional potential of his story. Too often he aims at our funny bones when he should be targeting our heartstrings. In the end, Walter Mitty is a film about acting out our dreams. But Stiller never quite shows us the soul of his dreamer. B-