Ben Stiller reinvents 'The Secret Life of Walter Mitty' as a fantasy-adventure with a love story at its center

The Secret Life of Walter Mitty, James Thurber’s 1939 sliver of a short story about a daydreamer trapped in a humdrum existence, had been adapted into film once before in 1947 as a musical, starring Danny Kaye as the eponymous hero who fantasized about all sorts of wild adventures. …