The 1950s ocean liner Queen Isabella is making her final voyage—a retro cruise from Long Beach to Hawaii and back—before heading to the scrapyard. For the guests on board, it’s a chance to experience a bygone era of decadent luxury, complete with fine dining, classic highballs, string quartets, and sophisticated jazz. Smoking is allowed but not cell phones—or children, for that matter. But this is the second decade of an uncertain new millennium, not the sunny, heedless mid-twentieth century, and certain disquieting signs of strife and malfunction above and below deck intrude on the festivities, throwing a trio of strangers together in an unexpected and startling test of character.