Twofour’s five part documentary, On Thin Ice, starts on Sunday 28 June on BBC TWO. Eighteen months on from completing their incredible Atlantic Rowing Race, Ben Fogle and James Cracknell are ready for another challenge. This time, they want to something even harder, bigger and more difficult… a race to the South Pole!

Described as one of the toughest endurance races on the planet, the challenge involves ski-racing 480 miles whilst pulling a 150lb sled, facing temperatures of up to -50C and negotiating crevasses, frostbite and severe physical exhaustion in one of the world’s most hostile environments.

As Polar novices, surely they have little chance of success against the more experienced teams, but their partnership has a fantastic drive, determination and competitive spirit – one which propelled them to success across the Atlantic. However, there’s another hurdle too as the South Pole Race is a 3-man event, so choosing the right person to complete their team could mean the difference between success and failure.

On Thin Ice (1/5)
Sunday 28 June, 9-10pm, BBC TWO
The first programme goes back to October 2007, 15 months before the race start, with Ben and James kicking off their training at The Great North Run. They then go on to experience the extreme cold for the first time in a climatic chamber. Here they face temperatures as low as -80C over a 24hr period.

The search is also on for the third team-mate. After weeks of deliberations, they recruit Hollywood actor and keen marathon runner, Jonny Lee Miller and together attend the first race training session in Arctic Norway. Facing stiff competition and blizzards is a baptism of fire for the three polar novices. But they pull through, bonding and having learnt new essential survival skills.

In programme 2 on Sunday 5 July as their training progresses cracks start to appear and Jonny drops a bombshell which could threaten the whole expedition.

On Thin Ice (2/5)
Sunday 5 July, 9-10pm, BBC TWO
As training for their Race to the South Pole continues, Ben Fogle, James Cracknell and Jonny Lee Miller run the London Marathon. But cracks are appearing in the team - Olympic athlete James is unhappy with Ben’s race time and doubts start to creep in about Jonny’s level of commitment. Then the bombshell; Jonny has to pull out because of a work contract. Ben and James are left high and dry, with only months until the race start.

With a frantic effort they hold a nationwide search for a new third team member, finally selecting Dr Ed Coats, a young and enthusiastic ex-decathlete. They start to work together as a new team, but it’s a slow process and a training trip to the Swiss Alps nearly breaks them apart.

Then Ben discovers he has contracted a potentially lethal disease... it looks like their Antarctic dream is over before it’s even begun.

On Thin Ice (3/5)
Sunday 12 July, 9-10pm, BBC TWO
With only weeks until they are due to leave, Ben Fogle is ill in hospital being treated for leishmaniasis vianna, a flesh-eating disease. His future in the race is highly uncertain.

His team-mates James Cracknell and Dr Ed Coats can only carry on with their training, hoping that Ben will recover in time whilst facing the real possibility of having to go without him.

With just days to go till they must leave the UK, Ben is finally given the all clear from the doctors. At last the team can come together and make final preparations for the race ahead in one of the toughest and most hostile environments on the planet.

They arrive in Antarctica, along with five other race teams and head off into the desolate icy wilderness for a ten day acclimatisation trek. Through Christmas and New Year they ski into some of the worst weather that this region can throw at them; fierce blizzards blow, the temperature plummets and emotions run high as the race start looms.

On Thin Ice (4/5)
Sunday 19 July, 9-10pm, BBC TWO

Its Sunday 4 January, 2009 – the air is full of cautious anticipation as the competitors finally cross the start line of this, the first organised race to the South Pole since Scott and Amundsen's historic journey almost a century ago. It’s been an unrelenting ride just getting to this point and now the team of Ben Fogle, James Cracknell and Dr Ed Coats must head off onto the Antarctic plateau where ahead lies 480 miles of sheer hell. They start off incredibly well, setting a blistering pace and actually leading the pack. But within days, the relentless cold, the extreme race schedule and sheer physical exhaustion start to take a serious toll.  James, the Olympic champion, struggles with severe blisters and the team must endure unexpected and dangerous crevasse fields. Their emotions start to run high as they tackle, step by step, the treacherous journey in front of them. It’s the hardest challenge of their lives and Ben, James and Ed begin to wonder if they stand a chance of even completing let alone winning the race. As they reach the halfway checkpoint, exhausted and near collapse, they have to face the real possibility of not being able to continue. James has deep blisters and a swollen face, his childhood asthma has returned and he has pneumonia in one lung – will the race doctors let him carry on?

On Thin Ice (5/5)
Sunday 26 July, 9-10pm, BBC TWO

The Polar novice team of James Cracknell, Ben Fogle and Dr Ed Coats wake up at the enforced 24hr checkpoint after what has been their first decent night’s rest since starting the race.

James must wait for the race doctor’s assessment to find out if he can continue or not. Finally, with a small pharmacy in tow, they are allowed to depart on the second and final leg to the South Pole.

They head off in good spirits, picking the pace up again and storming off onto the bleak and barren Antarctic plateau. But within days they face even more challenges. James discovers frostbite and the doctors must check if he is well enough to continue. When he faces near collapse, the team has to stop early as he breaks down in an emotional crisis.

This is exactly what they have spent months and months training for - not just the sheer physical endurance but the psychological bonding of friendship that makes or breaks an expedition this extreme. The team rally around and pull together, sharing the load and supporting each other.

In a feat of true camaraderie and endurance they jointly step forward and push onto the finish line, arriving in a state of exhaustion and near collapse. Battle scarred and wrecked they have nonetheless achieved the near impossible. James, Ben and Ed have conquered the South Pole.

They have crossed the finish line in an incredible second place having raced against five other teams of more experienced polar explorers. It’s been an unbelievable journey that has seen them reach incredible highs and hit the lowest lows but ultimately culminated in them fulfilling their dream of reaching the South Pole… alive and just about in one piece!

On Thin Ice is also available to view on the BBC HD Channel on Mondays at 9-10pm.

“utterly compelling” Sunday Times
“riveting” Radio Times
“…this is real life drama at its most gripping.” Mail on Sunday