In World War II, the Enigma was a German device that looked like a chunky typewriter with primitive electric lights; it could scramble messages into millions of different random codes. The legend of how the British cracked the almighty Enigma must have sounded, on paper, like a nifty mathematical thriller—a historic WarGames set at the formative moment of the computer age. On screen, however, Enigma plays as if the scriptwriter, Tom Stoppard, and the director, Michael Apted, were themselves cryptographers; they seem to be making hunt-and-peck stabs at how to translate a tale of arcane numeric formulas into drama. At Bletchley Park, where the British gathered their biggest and, in some cases, their most cracked eggheads, we meet Tom Jericho, a Cambridge genius played by Dougray Scott, looking even glummer than he did in M:I-2. In flashback, he ponders his fling with Claire (Saffron Burrows), a blond flirt who may have been a spy. Meanwhile, her frumpier roommate (Kate Winslet) helps navigate the code. ”Enigma” is a turgid muddle of romance, espionage, and geek valor, despite intimations that it might have turned into A Reasonably Dapper-Looking Mind.