It's being billed as a romantic thriller, but the most interesting aspect of "Enigma" are the details about the way the Allies struggled to crack encoded German transmissions during World War II. A similar theme is the basis for another new film, "Windtalkers."

Although new to Milwaukee, "Enigma," directed by Michael Apted and produced by Saturday Night Live's Lorne Michaels and Mick Jagger, who makes an appearance as an extra in a club scene, was released internationally in 2001.

Written by respected playwright and Oscar winner Tom Stoppard ("Shakespeare in Love"), "Enigma" is the story of an ace British codebreaker Tom Jericho (Dougray Scott, "Mission: Impossible II"), who is returning to work after a month spent on leave after suffering a nervous breakdown apparently caused by a shattered relationship with Claire (Saffron Burroughs), a stunning woman who also works in the Bletchley Park codebreaking complex 40 miles north of London.

In March 1943, Jericho returns, against the wishes of his former commander, to help solve a problem. His is the top codebreaking mind and he is needed to help decode a new German system that has successfully prevented the Allies from understanding their transmissions. Now three huge convoys of merchant ships headed to England from the United States are threatened by U-boats. Only by breaking the code can the attacks be prevented.

At the same time, Jericho learns that Claire has gone missing and this coincides with when the Germans changed the codes. Some people are suspicious, including secret service agent Wigram (Jeremy Northam), who is tailing Jericho and Claire's roommate Hester (Kate Winslet), who are breaking all kinds of laws to try and find out what happened to Claire. In the meantime, they unravel a series of betrayals, both personal and international.

The results are unexpected, certainly, but the romance is not terribly engaging nor is the story more than mildly thrilling. Most of the performances are adept, but none is spectacular. The result is a film that with its reserved romance and suspense -- and range of British accents -- would feel right at home on "Masterpiece Theater."

The most interesting bits relate to the Enigma machine created by the Germans and the ingenuity of British codebreakers. With its options for encoding, the Enigma machine's different permutations were so numerous as to boggle the human mind and create an unbreakable code. But the codebreakers at Bletchley Park created primitive computers that could test all of the millions of possible settings to break the unbreakable and, in the process, shorten the war and create the basis for today's computers.

"Enigma" opens Fri., June 7 at Landmark's Downer Theatre.