As the two sides begin to make good progress, host AJ Odudu presents them with a curveball - any team member can put themselves forward to switch beaches. At least one person from each group must move to their rivals, and if no one volunteers, then it's up to the team leaders who goes.

One of the teams is dealing with a betrayal after one of their own sabotages the build in exchange for some of the prize fund. The team's chances of being first to the money have never seemed so far out of reach. Luckily, there's a lifeline around the corner, as both teams are offered the chance to bid for a carpenter to join their ranks. But they're not bidding in money - they're bidding in the number of team members to go home.