Four days in, and the contestants are struggling. There's £100,000 hidden in the jungle, waiting to be found, but the group are busy battling sleep deprivation thanks to an insect infestation. Plumber Jack wrestles a potential meal from the grip of a python, and crisis hits when the islanders realise there is a major issue with their water supply. Ex-marine Marco and hereditary peer Ivar are sitting on a secret stash of £35,000. They volunteer to lead the search for a new water source - but can they be trusted to put the interests of the group before their own?