1. Episode 1

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

2. Episode 2

Alliances are formed in a test of endurance and memory.

4. Episode 4

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

5. Episode 5

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.