Graham takes on the Arctic Circle Race, a marathon 160km cross country trek through the beautiful wilderness of Greenland. Only the most determined and resilient competitors even make it to the starting line - let alone the finish.
Rugby legends Jeremy Guscott and Brian Moore then team up with Ed and Graham for a marathon ski race in Switzerland.
Both teams must ski all five ski areas between Davos and Klosters in one day. Brian will attempt the challenge off piste with Graham. Jeremy, a novice, will stick to the piste with Ed.
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