Thanks largely to his role as Grant Mitchell in EastEnders, Ross Kemp made a successful career playing the hard man. The man on the fringes of the law. A family man with a fiery temper and a tendency for violence. It was a role he was destined to play.

But then in 2004, he filmed his first documentary – Ross Kemp On Gangs – and these days Kemp is now more renowned for his investigative film work than he is for acting. He’s been to Afghanistan on the front line. He’s gone in search of pirates across dangerous trade routes. He’s exposed everything from homelessness, illicit trade and drug addiction to violence and poverty.

In his new series Ross Kemp: Mafia And Britain, which takes him from London to New York, Italy, Colombia and Spain, Kemp sets out to investigate and expose Britain’s surprising and deep-rooted links with the Mafia, dating as far back as the 1920s, and how our country even became a safe haven for “Cosa Nostra” lieutenants, “soldiers” and hit men who have hidden all over the UK in locations as unlikely as caravan parks and newsagents.

As part of his journey, he’ll also meet those closest to Mafia bosses, top organised crime investigators, and some who have been affected by their crimes. What he finds will enable him to create a historical map and timeline to reveal how the Mafia has quietly and effectively inveigled its way into the heart of Britain’s underworld.

Ahead of the start of Ross Kemp: Mafia And Britain, which begins at 9pm on Tuesday 10 September on Sky HISTORY HD (CH 131), Ross sat down with us to talk about the series:

Hi Ross! Have you always had an interest in the Mafia and organised crime?

Yes, because my dad was a copper. Organised crime groups haven’t gone away. They may not wear pinstripe suits and carry Tommy guns but they’re still here. And they’re still doing what they’ve always done historically, which is supplying human beings with what they hanker for.

What were you most surprised to learn while filming the programme?

The scale of it. It’s enormous. If you look at the definition of Mafia, it says it’s an organised crime group profiting from the black market in Italy, America and elsewhere. Well, elsewhere is everywhere. But that word, to me, has come to mean so many more different things.

Who do you think was the most powerful crime boss in UK history? Charles Sabini, Billy Hill, the Kray twins or someone else?

Well, they’re the ones that we know about. But the ones that we don’t know about are probably the most powerful ones because we don’t know who they are. The most successful gangster never sees a prison.

Did your opinion change of who the Mafia are in real life compared with media stereotypes such as The Godfather?

No, I think those films are incredibly close. But maybe not as violent and as bloody as the real thing. There’s a very dark and very serious side to it. Most people who end up in the American mob, the Colombian cartel or the Mafia are often born into it. They have no choice. And once you’re in it, you’re very unlikely to get out of it unless you turn state’s evidence or King’s evidence. And then after that you’re a marked human being. So, let’s not glamorise it and paint it to be something romantic. It’s far from it.

What do you enjoy more: immersive documentaries like these or acting?

I’ve been in television for 40 years. I have a strong hankering to go back and act and I’ve had a very varied career. One minute I’m up the Cauca mountains at 8,000 feet in the dark with no GPS, worried that we’re about to get kidnapped by FARC [Revolutionary Armed Forces of Colombia] and then the next minute I’m going, “Welcome to the Bridge Of Lies, where winning is as easy as getting from A to B.” 

Why should viewers tune into your new show?

People are fascinated by stuff that they don’t know about. But they don’t know how to find out about it. So I’m a conduit – that’s all I am. I go and meet interesting people or people that do interesting stuff and then I relay it back to an audience. I don’t think I’ve ever seen a programme that tackles and looks at this subject historically and tries to unravel it. This isn’t The Sopranos or Goodfellas, it’s the real thing. So that’s why you should watch it.

When can I watch Ross Kemp: Mafia And Britain on TV?

Ross Kemp: Mafia And Britain airs Tuesdays from 10 September at 9pm on Sky HISTORY. You can also catch it in Sky HISTORY on demand.

Want to find out more? Don’t miss Ross’s brand new book, Ross Kemp: Mafia And Britain, that’s based on his TV series and will be published on Thursday 19 September from Octopus Books.