Based on the best-selling novel by Robert Harris, Enigma is a British thriller set in March 1943, when the crypt-analysts at Bletchley Park are facing a nightmare.

The experts at Britain's top code breaking centre must decipher the codes of the Nazi's U-boats, which have suddenly changed course and put an Allied shipping boat, with 10,000 people on board, at risk.

Tom Jericho (Scott) is a brilliant young mathematician who is called upon to help break the new codes.

He is also recovering from a nervous breakdown, relating to a failed relationship, which led to an enforced leave of absence.

Tom is intrigued by the job but is preoccupied with another mystery. Claire (Burrows), the object of his desires has disappeared amidst rumours of the presence of a spy in Bletchley Park.

Claire's room-mate Hester (Winslet) tries to help him solve both mysteries.

The stylish directing of Michael Apted complements an intelligent script by Tom Stoppard.

It's engrossing and literate and draws the audience into a world of intrigue and fear, a world very real for many Britons alive today.

The period detail is perfect and the historical statements are accurate (unlike last year's U-571, based loosely around the same subject), yet still manage to fit well with the dramatic conjectures.

The plot twists and turns, which can only be credited to Harris, but the cast is superb in each of the major roles.

Scott and Winslet, in particular, come together to create an edgy, atmospheric period piece with a sense of urgency and imminent danger but little panic, in a truly British fashion.

Scott is in his element in his first lead role and looks duly haggard and depressed, with an extremely engrossing and believable manner.

But his innevitable romance with his sleuthing partner, Hester, seems out of place, given his obsession with Claire.

War-torn 1940s Britain is depicted as the grey and miserable place it was, but the hope and optimism in the characters gives the film a truly compelling and original feel.

Produced by Mick Jagger's Jagged Films, the star himself even makes a cameo appearance as an officer with a couple of ladies on his arms.