[ad name=”468×60-text-film-ad”] Watch the full-length trailer for The Secret Life of Walter Mitty. Ben Stiller, Kristen Wiig and Sean Penn star in the remake of the 1947 Danny Kaye comedy based on James Thurber’s short story. See the new movie trailer, posters, movie photos for The Secret Life of Walter Mitty below. Walter Mitty (Stiller)…