The Big Adventure (2014)

Set on a tropical island, hosted by Jason Dundas, a cast of twelve contestants competed for AU$1,000,000. A grid of 25 squares was set up, 12 of which contained keys. Contestants competed in a series of tasks for the right to dig for a key. Each episode one contestant would dig and one would (usually) be eliminated. In the last episode, four remaining contestants used their keys to open chests, one of which contained the prize money.