Celebrities compete in athletic challenges for a share of a £100,000 prize fund.

Model and reality star Arabella Chi faces a dilemma: will she stay loyal to an old friend?

Alliances are formed in a test of endurance and memory.

One player questions if her friendship is worth risking £50,000 for?

Host Mark Wright presides over the Final, as the remaining Challengers race across the Argentinian countryside for their share of £100,000, and to be crowned Challenge UK Champion.