Sir Ranulph Fiennes might just be the most intriguing man in the world.

As a young demolitions expert in the British Army, Fiennes was arrested trying to blow up a dam built by 20th Century Fox for the film Dr. Dolittle because he thought it was ugly. In 1969, he rode a hovercraft up the churning croc-infested waters of the White Nile in East Africa. In 1993, he became the first human to ever cross Antarctica unsupported. Seven years later, he amputated his own frostbitten fingers during another unsupported trip — this time to the North Pole.

Guinness World Records calls Sir Fiennes the world’s greatest living explorer. At 68 years old, he continues to live up to that title. Last month, Fiennes announced he and a team of six adventurers aim to become the first humans to ever cross Antarctica during the dead of winter. The expedition, called The Coldest Journey, will take off from London in early December and last more than six months, taking the team into all-day darkness and temperatures close to -90° C (-130° F).

There’s a reason nobody’s ever crossed the Antarctic in winter before. Just look at the 2,000-mile route. It’s a challenge to even conceive of crossing that terrain at the coldest time of the year.

But Fiennes doesn’t think he’s the only explorer thinking about crossing Antarctica in winter. “We heard a rumour that Norwegian explorers were contemplating this,” he tells BBC News. “We realised we were going to have to have a go.”