Standing in a spectacular Shakespearian theatre, the words "time- warp" spring to mind. The elevated seats are empty, but below on stage, a vicious duel is being played out by two men with a range of theatrical swords and daggers.

Perspiration is pouring from both combatants as they circle one another, feigning and lunging, until they both end up wrestling on the floor. At Shepperton Studios, the duel is played out by two stuntmen working on the new motion picture, Shakespeare in Love.

Among others, William Hobbs directed the fight scenes in Rob Roy, Mel Gibson's Hamlet, and Cyrano De Bergerac. Today he's choreographing one of this film's fight scenes. It's his job to make the scenes believable, fluent and most importantly, dramatically exciting.

"Mel Gibson's duel in Hamlet took three weeks of planning and rehearsal before shooting," he explains. "It starts with the scripts, talking to the director and meeting with the arts department. Then I start planning."

A background in fencing and theatre (as an actor) enabled him to see a potential gap in the film production process. "It seemed to me that there was a niche there that had never been fully developed." His first assignment involved working on Zeffirelli's Romeo and Juliet. At the start of his new career, there was no such thing as a "fight director" and no drama schools which taught staged combat as part of a structured curriculum.

Back at Shepperton, they're ironing out the details of the fight sequence. "When we get to this part on the floor where should the dagger be?" asks stuntman Mark Southworth. Climbing on stage, Hobbs runs through the sequence with Southworth and the other stuntman, Paul Jennings (right).

It's similar to a choreographer leading dancers through a complex arrangement. In super-slow-motion they move around the stage, jumping off ledges and darting behind pillars. Every movement is broken down; feign, parry, lunge - right down to the point where they lose their weapons.

Realism is only part of the process. The actors playing the roles are also taught. And Hobbs must also ensure that the weapons and methods of combat are as historically accurate as possible.

"The further back in time you go, the less we know about techniques of the period, so I'm very reliant on looking at pictures and prints to get a flavour," he says.

"We don't really know what went on during this time. How good were the plays in Elizabethan times compared to modern theatre? Were they more stagey than we would expect now?

"With this particular film, my dilemma is finding the right balance that is historically authentic and appealing to a modern audience."

One of Hobbs's most memorable scenes was the climax of Rob Roy where Liam Neeson's hulking Scottish character faces the English dandy, played by Tim Roth.

"Tim's character was much smaller and it had to be believable that he could defeat someone as enormous as Liam Neeson - that was a big challenge.

"When I started to work on the scenes, it occurred to me that the fight was working because Roth's character never finishes his opponent off when he has the chance. He delays and delays like a cat playing with a mouse and suddenly I knew that that was the way to go."

Hobbs works with some of the biggest names in films (Shakespeare in Love stars Gwyneth Paltrow and Colin Firth) - unfortunately, he's too professional to reveal who was a pain in the neck.

The scores of people who flocked to watch Leonardo DiCaprio in The Man in the Iron Mask can sample Hobbs's most recent work, though you're unlikely to find him sitting next to you in a cinema after a previous episode left him emotionally scarred.

"The only time I watched a film that I worked in was when I was in a hotel years ago. Some children were watching a Hammer Horror film in which I appeared as a vampire, and I was getting quite embarrassed. At the end, one of them looked at me and said, 'That must be the worst film I've ever seen'." It seems everyone's a film critic.

Stage fighting is now on the curriculum, as part of wider stage schools' courses, at the following drama schools:

Central School of Speech and Drama: 0171-722 8183

Royal Academy of Dramatic Arts: 0171-636 7076

London School of Musical Theatre and Drama: 0171-976 1656