Sweden: Otillo Swimrun World Championship (S03E09)

Ötillö, the origin and pinnacle of the latest ultra-racing phenomenon, features an extraordinary challenge that blends 10 kilometers of swimming with 65 kilometers of running across 26 islands in Sweden's Baltic Sea archipelago. Competitors team up to navigate the slick, treacherous terrain of the islands, which intensifies the challenge. Yet, it's the daunting swimming stretches and unpredictable sea swells that truly test the limits of each racer, culminating in a sudden and devastating conclusion for one unfortunate team.