David Hughes and John Murphy, Liverpudlian composers and musicians who always work together, have sold an astonishing 90,000 albums of their soundtrack for the violent gangster film, which stars Vinnie Jones. (The soundtrack of another recent cult movie, The Wedding Singer, sold 45,000, and the British hit Sliding Doors has sold only 20,000.)
Now Hughes and Murphy are negotiating with New Line for the job of scoring The Bachelor, a big-budget romantic comedy starring Chris O'Donnell and Rene Zellwegger. The screenplay has been written by Gary Sinyor, the writer behind the British comedies Leon the Pig Farmer and Stiff Upper Lip.
Hughes and Murphy take unusual routes to create their effects. In Lock, Stock they created the tense build-up to a gangland fight with the incongruous Zorba the Greek theme.
"I had to learn to play the bouzouki overnight," says John, 33. "It is such a fast piece of music that we had to edit the soundtrack together."
The pair shy away from musical cliches established since the Fifties. "The trouble is that a lot of them became cliches precisely because they work," says John. "What's more, composers tend to come in on a film project towards the end, at a time when the director is often feeling a little under-confident and jumpy. You need a brave director to allow you to be different."
Alexander Stonor Saunders, a director of Soundtrack Music Associated, manages Hughes and Murphy and put them forward for Lock, Stock.
"The score for Lock Stock and Two Smoking Barrels would have been a loose and ineffective coalition of songs without David and John's original score," he says.
Their career in film music began after a chance encounter with would- be director Vadim Jean. Hughes and Murphy were offered the task of scoring Leon the Pig Farmer.
"When Vadim told us we had the job, we ran into Charing Cross Road to Zwemmer's, the musical bookstore, to find a book about how to compose music for a film," says John.
Now the offers are coming in fast. Hughes and Murphy hope to make a comedy with Pilgrim Films called The Bum's Rush.
And they have also just sold their own screenplay - about a man who accidentally makes it big in the film business.