Dougray Scott is an actor who likes to make his life as difficult as possible. In This Year's Love, playing a painter, he rolled up his sleeves and created all the artwork himself.

Before filming started on Mission: Impossible 2, in which he was cast as the villain, he picked the brains of specialist US Navy Seals and subjected himself to a seven-month fitness programme, including 45 hours' gun training.

For his starring role in the upcoming Enigma, he plays Tom Jericho - the brilliant codebreaker at Britain's World War II deciphering HQ Bletchley Park. For the part, he studied the relevant mathematics and became so familiar with producer Mick Jagger's Enigma machine that he took it to pieces and reassembled it.

In Robert Harris's admirable thriller, Jericho is the public-school-educated son of a bridge-crazed mother from the Home Counties. In Michael Apted's equally enjoyable film version, which also stars Kate Winslet, Jeremy Northam and Saffron Burrows, Jericho is quite a different beast. 'I came up with the idea of making him come from Manchester,' says Scott, 35. 'I think it makes it more interesting to make him come from an educated working-class background. Otherwise, there's an alienation that comes from him being not just a genius mathematician, but also a posh kid.'

So, Scott provided the detailed backstory (Manchester Grammar, a Cambridge scholarship, etc) that goes entirely unmentioned in the film itself. 'But having that story is really important to me when I'm creating character on film. It gives depth of character,' says Scott. The suspicion must be that Scott's obsessive, muscular work on every project he has ever been associated with, from disposable popcorn blockbuster to arthouse orchid, stems from a need to justify his success in an industry far removed from the Fife docks, where many of his old schoolfriends now work.

Scott (christened Stephen but there was already a Stephen Scott in Equity so he took his grandmother's French surname, Dougray, instead) grew up in a Glenrothes council house, the son of a nurse and a refrigerator salesman. At 14, he read Death of a Salesman, which led him to the Welsh College of Music and Drama, and then to roles in Soldier Soldier, The Crow Road for TV, and then to films: Regeneration, in which he played Robert Graves, and the Drew Barrymore vehicle Ever After, in which he was imaginatively cast as Prince Charming.

Next up, he is opposite John Malkovich in Ripley's Game, an adaptation of Patricia Highsmith's novel . Enigma is the biggest project he has headlined, but the film is in danger of being overshadowed by rumours, hotly denied, that he played a part in his co-star Winslet's marital split.

Enigma opens on 30 September

Five things you need to know about Dougray Scott

1. Trained at the Welsh College of Music and Drama.

2. He was named Most Promising Student at college.

3. Supports Hibernian football club.

4. Cast in X-Men but opted for Mission: Impossible 2.   [Ed. note: this is incorrect.  See FAQ]

5. Actually born Stephen Scott.

© Guardian Newspapers Limited 2001

- Thanks to Gill for the find!