Comedian Sue Perkins and adventurer Charley Boorman travel across Alaska to the notorious Dalton Highway, where avalanche units operate throughout the year.
Comedians Rhod Gilbert and Greg Davies attempt to drive through the mountainous, landlocked nation of Nepal, starting from the chaotic border with India.
Adventurer Ben Fogle and comedian Hugh Dennis drive a historic route from the Peruvian Andes to the depths of the Amazon. They hope to find the lost city of Constitucion.
Good friends and fellow comedians Ed Byrne and Andy Parsons brave temperatures as low as minus 50 to drive across Siberia's infamous Road of Bones.
Sue Perkins and Liza Tarbuck drive the legendary Ho Chi Minh Trail, a network of dangerous roads hacked through the mountains and jungles of Laos and Vietnam.
Hugh Dennis and David Baddiel make their way along over 1,200 miles of dangerous roads in Ethiopia on a journey to Aksum, the country's most holiest place.
Driving up Madagascar's eastern coast at the tail end of the rainy season is enough to test the best of friends. Angus Deayton and Mariella Frostrup are game enough to take on the challenge and luckily, good enough friends to poke fun at each other as the road puts them to the test. It is a route with countless river crossings, offering Angus and Mariella a terrifying variety of broken bridges and flimsy ferries as the only way across. The roads themselves are mired with thick mud, making progress increasingly painful, until finally the road gets the better of them and they are forced to spend a night in the car.
Hugh Bonneville and Jessica Hynes were a perfect match in BBC Two's comedy hit Twenty Twelve. Now they pair up again for a terrifying road trip through the former Russian state of Georgia. Driving from the border with Azerbaijan to the Black Sea, Jessica soon discovers her spirit of adventure causes Hugh a few moments of high anxiety. Yet Hugh realises that there is plenty more to come as they find themselves stuck on a high mountain pass in bad weather and he must overcome his vertigo. While the drive is a challenge all the way, the pair are transported into a land that time forgot as Georgia and its people delight and surprise them at every turn.
Funny men Phill Jupitus and Marcus Brigstocke head to Bolivia for a high-altitude road trip that promises adrenalin, hilarity and drop-dead beautiful scenery. Already good friends, the terrified duo first have to survive Bolivia's infamous Road of Death only to find themselves deep in notorious bandit country. Disorientation takes them by surprise as they have to navigate the stunning Salar de Uyuni, a salt lake so vast that Buzz Aldrin could see it from space. Their goal is to reach the ancient mountain city of Potosi whose silver once financed the great Spanish empire but at almost 5000 meters above sea level this proves to be a heart stopping finale.
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...
Rhod Gilbert and friend and fellow comedian Angela Barnes cross Italy's most treacherous Alpine roads in Rhod's first adventure since being treated for cancer.
Joe Swash and Seann Walsh are no strangers to jungles after appearing on I'm A Celebrity..., but neither of them has sought an ancient Mayan temple in Guatemala before.
Former Soccer Saturday buddies Jeff Stelling and Chris Kamara reunite for an epic journey across Sri Lanka where they reaffirm their friendship along the way.
Mike Wozniak and Ola Labib head to one of the wildest places on Earth - the Namib desert - to meet for the first time and have each other for company on their journey.
David Harewood and best friend Fraser James swap the sets of Hollywood for a new challenge in Slovenia where they face some of the most dangerous roads in Europe.
Jess Fostekew and her good friend and fellow comedian Desiree Burch take on an utterly insane trip across Colorado's Rocky Mountains in a Wild West adventure.
Jamali Maddix and Larry Dean experience the Land of the Thunder Dragon, a place of mystery and wonder in the rarely-visited and remote kingdom of Bhutan.
Olga Koch and Thaniya Moore - who are friends from the comedy circuit - head to Bulgaria for a high-octane adventure that takes them across two epic mountain ranges.
