Series 4

Actor Will Mellor cajoles one of his best mates - comedian Keith Lemon - to join him on a high-octane road trip in Albania.

Another thrill-seeking adventure, this time with long-term mates Joe Wilkinson and Zoe Lyons - who've travelled to gigs together for years - taking on the wilds of eastern Turkey.

Certified 'indoorsman' Phil Wang convinces best friend Pierre Novellie - also not much better at outdoor stuff - to join him in Africa's Kingdom in the Sky.

Another thrilling escapade in the wild - this time sees actor Stephen Mangan and comedian Lara Ricote, who have never met before, aim to reach the northernmost point of Australia.

Ed Gamble and Lou Sanders have been friends for years, so much so that she's bought a 'his 'n' hers' set of driving gloves to tackle a dangerous 1000 kilometres of Iceland.

Jamie-Lee O'Donnell and Saoirse-Monica Jackson, who are best friends and stars of the hit sitcom Derry Girls, head way out of their comfort zone as they tackle rugged Romania.

Darren Harriott is a former bouncer and self-confessed city boy, while Ria Lina is full of adventurous spirit with a PhD and autism. How will they fare travelling in South Africa?

Comedians Maisie Adam and Suzi Ruffell wouldn't call themselves road aficionados - it took 10 goes to pass their driving tests between them - but they're tackling Morocco anyway.