Think of The Secret Life of Walter Mitty as a movie version of those ubiquitous Metro ads advertising cheap flights from D.C. to Iceland. In this adaptation of James Thurber’s famous 1939 short story, Ben Stiller (who also directs) plays the eponymous hero, a shy photo editor at Life magazine who spends most of each day lost in his elaborate fantasies. When he loses a crucial photo intended for Life’s final cover (before it goes digital), Mitty’s action-filled fantasies come to life as he travels the world—including an extended stop in Iceland—to track down the elusive photographer who took it. The comedy is slight, especially for Stiller, who helmed the edgier Zoolander and Tropic Thunder. He aims for something more inclusive here and mostly achieves it. While the characters are thinly drawn, the cinematography is gorgeous, the tone is genial, and the message—that we should all put down our devices and go live a little—should please even the most iPhone-attached viewers. The film shows at area theaters beginning Dec. 25. See Page 59 for showtimes.