Ross Kemp on turning game show host with Bridge of Lies: "Old dog, new tricks!"

"There is a snob factor probably from some people. That's entirely up to them. I don't really care what people think. If I think it's good, then that's good enough for me."

Kemp is the host of new BBC One daytime quiz Bridge of Lies, which sees teams looking to win a cash prize by navigating their way across a 'bridge' by stepping only on the correct answers. Example: if the theme of the round is "Disney films" and they step on "The Lion King", they're safe, but if they step on "How To Train Your Dragon" (produced by DreamWorks), they're in trouble.

The treatment for the show "just lifted off the page" according to Kemp – and he also had a pre-existing relationship with producers STV from ITV's 2017 documentary Ross Kemp Behind Bars: Inside Barlinnie. On top of that though, the challenge of doing something radically different appealed to him. "I knew there'd be people saying, 'Ross Kemp can only do documentaries', or 'he can only be Grant Mitchell' – so it's a little challenge to Kemp, in his dotage, to see if he can do this."

Kemp says he "worked hard" to perfect an on-screen persona that would work for Bridge of Lies. "I observed a lot of the people who I think are very good at [hosting game shows] and trust me, it isn't as easy a gig as people might like to think. I've got a newfound respect for these presenters, because the dynamic can often change very quickly and you've got to adapt to it."

He lists The Chase host Bradley Walsh, Pointless presenter Alexander Armstrong and Tipping Point's Ben Shephard as his inspirations. "I don't know them very well but I've spent a bit of time with each of those three people and they are individuals in their own right and they bring their personality to that particular game show and I think, in terms of my physicality, I am the right person for Bridge of Lies.

"I didn't take anything from anyone else, because if you start doing that, you're just trying to replicate something else. You've got to be organic and true to the self."

Having transitioned in his career from actor to BAFTA-winning filmmaker, Kemp is used to taking a leap into the unknown, but admits that this latest career switch-up proved more challenging than he first expected. "Having been around the world a bit, I've been in more jeopardous situations than crossing a bridge in a studio, but I get wrapped up in it very quickly, particularly if... and I honestly mean this, there wasn't one group that I did not like.

"It wasn't like talking to a complete stranger – everyone seemed very relaxed with me and consequently I was very relaxed with them, and I think that comes through."

Resisting the urge to help his quizzers, particularly when they made obvious missteps, proved difficult. "It was so hard, because it's not a format that I'm used to. I can only say, 'Think about it, take your time'."

On a practical level, working on a busy studio floor and communicating with the show's production team via an earpiece was another new experience. "I wasn't used to people yabbering in my ear, telling me what to do. I'm used to being on my own in a very small outfit. It wasn't like that obviously at EastEnders – there were lots of people telling me what to do and then I went off and did exactly what I wanted to do most of the time... within the lines given!

"So it was a totally different format, a totally different way of working."

• Ross Kemp wants soaps special of BBC game show Bridge of Lies

The game itself is also more involved than you might expect, according to Kemp. "It does appear very simple on the page, but the complexities of how you play it and the strategy involved in it is a bit more complex than just hoping you're going to step lucky.

"Some of the developers and the people who worked on it at STV, we would play it, it's such a good game. I would host it and they would play it and you'd watch... there was a lot of cockiness before a fall, mate. It's a humbling game."

Kemp himself believes he'd fare quite well if he took on the Bridge of Lies, which he credits to the wisdom that comes with age. "The 25-year-old Ross Kemp would play Bridge of Lies very differently to the 50-year-old Ross Kemp, because the 25-year-old Ross Kemp would be very cocky, he'd think he'd know everything... and then he'd get halfway across and he'd be out of the game, whereas the 50-year-old Ross Kemp would take his time a bit more, be a bit more strategic and just concentrate on getting across, with however much money I could amass. So that's sort of the Ross Kemp philosophy of Bridge of Lies."

The final product is, he suggests, "entertaining TV on lots of different levels", combining a quiz with the physical element of crossing the bridge as well as a "sort of Gogglebox social interaction of families and colleagues" – with teams of four taking on the game one at a time, the remaining team members remain locked away in a green room, observing their teammates and commenting on their decisions but unable to advise or interfere.

Kemp hopes that more of these interactions to make it to the screen in future if Bridge of Lies runs to a second season, explaining that a number of fun moments shared between teammates ended up on the cutting room floor. "It's about getting a format over to an audience. There was so much stuff that hit the floor because of getting the format across that was hilarious, and very revealing.

"I said, 'Oh, why didn't we have this moment?' and they said, 'Because we're trying to make sure people understand what the game's about, Ross' – and that is quite important!"

Before a potential second series of Bridge of Lies though, Kemp is back on more familiar ground with a new documentary project – Sky History's Ross Kemp: Shipwreck Treasure Hunter will air next month and sees him dive in hazardous environments to discover secrets that lie beneath the sea and uncover hidden treasures and history from Britain’s past. "It's a totally different kettle of fish," he says. "My year couldn't have been more diverse."

Though he's accompanied by experts on his dives, Kemp had to train for months to qualify as an advance rescue diver for the documentary, which he says is being eyed as a possible returning series.

"There were some hairy moments," he revealed. "We dived at one point in a force eight [wind]. It was a real experience.

"It was jeopardous in places – it really was, properly. But it was also incredibly rewarding as well. I got it – I got what treasure hunters get from it, spending their afternoons with a metal detector, because there is an incredible sense of being directly in touch with the past in a way that I've never felt in a museum."

Uncovering lost history can be exciting, but also sobering, with Kemp noting that Shipwreck Treasure Hunter won't shy away from the darker side of British history – one discovery, for example, sees the team uncover anti-personnel guns "made specifically to spray shot against a mutinous crew of enslaved human beings".

"Hawkins [John Hawkins, 16th century naval commander] was one of the richest men in the world at the time, on a Bill Gates kind of scale, and made the majority of his fortune from the transportation of enslaved people – that's not something that you find when you pick up your history books," he says. "Particularly at secondary level. And it's really important that we should talk about our history and not avoid the bits that we find uncomfortable, because they're factual."

It's a very different project to a game show, though not without its own technical hurdles to overcome. "That's a new skill – doing pieces to camera underwater! Even when there's bullets whizzing around, I can sort of do that, but it was totally different to anything that I'd done before. But here I am – old dog, new tricks!"

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Bridge of Lies begins on Monday, 14th March at 4:30pm on BBC One and iPlayer, and continues daily. Visit our Entertainment hub for more news, interviews and features, and find something to watch now with our TV Guide.

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