The true story of a major breakthrough in intelligence technology created during World War II provides the backdrop for this blend of mystery, romance, and espionage, based on the novel by Robert Harris. Tom Jericho (Dougray Scott) is a gifted mathematician who is working with the British government on the development and maintenance of the Enigma machine, an electronic device that allows Allied intelligence agents to decode scrambled messages sent by Germany military officers. But the emotionally fragile Jericho is buckling under both the pressure of his work and the collapse of his relationship with Claire Romilly (Saffron Burrows), a co-worker with whom he's fallen deeply in love. After suffering a minor breakdown, Jericho is sent on a leave of absence, but when he returns to work, a crisis awaits: it seems the Germans have instituted a new code that the Enigma is not yet able to crack, and Jericho is needed to help unravel Axis communiqués before an important convoy of troops and materiel sets sail. It is also suspected that a German undercover agent has infiltrated the Enigma project, and Wigram (Jeremy Northam) is determined to ferret them out. In the midst of all this, Jericho receives troubling news that Claire has gone missing -- and that a file of German messages waiting to be decoded was found at her home. As Jericho works against the clock to crack the new German code, he forms an initially uneasy alliance with Hester Wallace (Kate Winslet), Claire's roommate and a fellow member of the Enigma project, as they try to discover Claire's whereabouts. Enigma was co-produced by Mick Jagger, who has a keen interest in the history of the real-life Enigma project, and even owns one of the original Enigma decoding machines.