:Ross Kemp Interview:

Ross Kemp was so determined to get fit for the role of Henno Garvie that he ended up with a broken foot.

"I went running around Battersea Park each morning for eight miles. Unfortunately I got a march fracture from the continuous pounding, so I had to go on the training weekend organised by Chris Ryan with a broken foot.

"Despite that, the weekend was a great experience. Chris taught us surveillance and survival - how to camp in the middle of the night and make sure you are not being followed. I must have bored the pants off him because I was constantly asking questions.

"In the morning, Chris came over and asked us if we wanted a cup of tea. When we all said yes he just laughed in our faces. But afterwards, he was always on hand to advise us during filming. I can't thank him enough."

Ross believes the mysterious world of the SAS has great appeal as a TV series.

"On television we’ve had everything from firemen to policemen to dustmen. We've had people who work on an oilrig and people on a lifeboat. No one's tried to tackle the SAS but I can't think of another job that's more dramatic or with more action. I think it will appeal to both men and women.

"The SAS is a secret organisation and they’re the elite - it's the hardest regiment to get into in the world. These people put their lives on the line for my freedom and if I had a hero in my life it would be one of these guys. But they don't tell anyone what they do and they don't expect praise. So it's very humbling to try to play one of them.

"Henno is paid to kill people and spends all his time training to do that, which does make him a bit cold-blooded. He has a softer side in the way he is protective towards his men, especially Jamie. I am more emotional than him. As a child I wanted to be a soldier, and I love playing Henno - but I couldn't be in the SAS and I couldn't kill anyone.”

Adds Ross: "They don't show it, but killing does affect the real troopers, so black humour is the way they have of dealing with it, just as it is with nurses and doctors. They experience life and death at a faster rate than other people do."

As part of the preparation for ULTIMATE FORCE, Ross learned how to fire weapons, use explosives and stun grenades and dismantle a gun.

"We were taught how to strip a gun down and reassemble it, and we were shown how to use harvey wallbangers, which are explosives that can bring down a brick wall. In the chaos and darkness afterwards, the SAS guys come in with their respirators like Darth Vader and their infrared lights and identify the bad guys.

"Obviously it's not a documentary and we have to work within budgets and time, but we're as technically correct as possible, and I'm very proud of the firefights. I get shot three times in one episode and I'm back running around, so we're obviously bending the truth, but it has to entertain people, too."

Ross swapped his SAS gear for a Father Christmas outfit when he was invited to 10 Downing Street for a children's Christmas party during filming. "I was put on a motorcycle with the red suit and beard flying and was at Downing Street half an hour later. It was worth it just to see the kids' faces."

Essex-born Ross is one of Britain's favourite actors. After nearly 10 years playing Grant Mitchell in EastEnders, he left to take up an exclusive contract with ITV, where his roles have included Without Motive and Hero of the Hour and the forthcoming dramas A Line in the Sand and The Crooked Man.

"Life is good and I really appreciate what I've got. On Ultimate Force we did a scene at Liverpool Street Station, where, had I not become an actor, I would probably have been coming each morning on the train to an office in London. In the close-up I was thinking how lucky I am."