Interview: Ross Kemp is back in the line of fire for Extreme World

EastEnders fans are in for a treat, as Mitchell family matriarch Peggy, played by national treasure Barbara Windsor, gears up to return to the Square for a special 30th anniversary episode next month.

But, setting aside hopeful rumours, Ross Kemp, who played her hard man son Grant Mitchell from 1990 until 2006, says he's too busy tackling real-life drama to go back to Walford.

"I can't join her," he says apologetically. "It's just about space in my diary - although I would never rule out going back to EastEnders, I owe it a heck of a lot. I think it's a great show."

Kemp is just finishing up filming his fourth series of Extreme World, the hard-hitting documentary strand that's seen him meet child soldiers in the Congo, investigate sex trafficking in Mumbai and, last year, held at gunpoint in Papua New Guinea.

The new series is no exception to events that have left the 50-year-old gob-smacked. In the first episode, he travels to eastern Ukraine to meet the neo-Nazi militia, whose ultra-right ideology is gaining worrying influence. Next, he heads to South Africa, to investigate a national rape epidemic that is claiming 500,000 victims a year, nearly half of whom are children.

"It's not my job to judge, but it's very difficult to be non-judgemental when it comes to rape, or child rape, particularly when people are openly admitting to it and high-fiving about it while you interview them. You can see on my face, I'm completely blown away by that.

"I keep asking them, 'What about the victim?' Each time, they bring it back to themselves; 'Oh we worry she could go to the police, we worry she could give us HIV'. My mouth was on the floor."

Though visibly aghast at the memory of these chilling interviews, Kemp's clearly besotted by his work. He calls his production team "the real heroes", adding they "have a knack at being in the wrong place at the wrong time".

"We arrive in Ukraine, and I'm out of the hotel and we're in a march!" he recalls. "The next minute we're in a full-blown [riot], chains are being hit against police, flashbangs [grenades] are going off at my feet, rocks and paving stones being broken up and hurled at the Rada [the Ukrainian government building] and I'm going, 'Hang on, I haven't even had my breakfast yet!'

"That's the excitement and exhilaration of doing a programme like this. It's a rarity and a privilege, and I'm continuously slapping myself in the face."

Born in Essex and trained at the Webber Douglas Academy of Dramatic Art, Kemp has moved on from his Mitchell days to earn a stellar reputation as an investigative journalist. He won a Bafta for his adrenalin-fuelled Ross Kemp On Gangs series, and his work in Afghanistan was so comprehensive that a British Ambassador in the country once described him as "the best war reporter" of all.

Now that British soldiers are finally home after 13 years of combat, what does Kemp think about it all?

"Was the blood and the treasure worth the lives? I would suggest not. I don't think you can ever quantify what other people have been through. It has certainly changed my life," he says.

"There have definitely been [improvements] in terms of education, particularly for girls. There's still chronic unemployment, the country is still divided, as it always will be between certain ethnic groups. It's great the elections have happened. I have a great admiration for the people, and I would go back there tomorrow if I could," he adds.

With the extreme human trauma the actor has witnessed, it's hard to imagine how anyone could forget about it each night, but Kemp is reassuringly smiley and composed.

"A lot of people say I should seek counselling," he notes. "I think that's probably a good idea at some point, [but] I haven't got time right now. I think anyone who goes through a lot of trauma should do that - but I'm not really in it, I have an escape route."

When it comes to relaxation, he says he is happiest "at home", and when he's not working, he enjoys "going for walks in the country, the odd glass of wine", and, all-importantly, "sleeping".

"How much longer I can do this, I don't know," he confesses. "Not from my mental capacity, but in terms of the fact that I'm 50 years old now! I enjoy being with my family."

Once married to ex-News of the World editor Rebekah Wade (later Brooks), Kemp also has a four-year-old son with a former girlfriend. In 2012, he married Australian corporate lawyer Renee O'Brien, who he affectionately refers to as "an intelligent lady".

While the rest of his family is "quietly proud" of his work, Kemp insists they don't allow him a swollen ego.

"My brother has made lots of films in hostile environments, my father was a soldier and police officer, so there's no bragging rights in our household, that's for sure! Everyone gets slapped and put in their place!"

Having fallen into film-making "by mistake", Kemp's goal - alongside making great television - is to create "a wider understanding of the situation that exists in the world". He is an active patron of Help For Heroes, but is clear it's not his job to change policy - "that's for governments to do".

So if EastEnders is ruled out for the time being, is there any chance we could see him pop up on a reality show?

"Never say never", he says, grinning. "The Ross Kemp motto is basically, don't decline to do anything until you're in the situation where you desperately have to do it!"

Cryptic philosophies aside, for now, he's relishing the opportunities that Extreme World has given him. In this series, he rides a Harley-Davidson with the Rebels Motorcycle Club in Australia, from Melbourne to Canberra then Sydney. "Luckily I was wearing a crash helmet, or my bald head would have burnt to a crisp!" he jokes.

"The freedom that we have is just unbelievable. How lucky am I, to have had a career as an actor and be doing what I'm doing now?" Kemp adds. "Don't think for a second that I don't thank my lucky stars every day."

EXTRA TIME - HARD-HITTING DOCUMENTARIES

:: Food, Inc. (2008) - Documentary-maker Eric Schlosser reveals how corporate farming in the USA sacrifices animal welfare and health and safety for cheap food production. You'll never look at dinner the same way again.

:: Bowling For Columbine (2002) - Award-winning film-maker Michael Moore explores the US gun culture that sowed the seeds for the 1999 Columbine massacre, when two teenagers murdered 12 fellow high school students.

:: Shark Bait (2011) - Foul-mouthed chef Gordon Ramsay travels to China and Costa Rica to take on the cruel shark fishing industry, which slashes millions of sharks of their valuable fins before throwing them back into the sea.

:: Clothes To Die For (2014) - A shocking expose of the Bangladesh garment industry through the eyes of survivors of the Rana Plaza factory collapse, which crushed 1,130 workers in April 2013.

:: Grizzly Man (2005) - The heart-wrenching story of Timothy Treadwell, a conservationist who spent his life filming and living with wild Alaskan grizzly bears, until tragically, one killed and ate him.

:: The fourth series of Ross Kemp: Extreme World begins on Sky1 on Thursday, January 22