S1·E2 Down Under

Herbert and Neb find Captain Harding alive in the cave but he has no memory of how he got there, only of slipping below the waves after jumping from the balloon. Reunited, Harding, Spilett and Neb decide to climb to the top of a mountain to get their bearings. Along the way they stop at a pool where Spilett takes a swim only to get attacked by an unseen creature, eventually escaping to the safety of the shore (with help from Nemo). Meanwhile, Jack and Herbert go off hunting but Herbert can't bring himself to kill. They come across a cave and inside they find an alter and a gold plate. They become trapped when the entrance closes up. Unable to dig their way out and with hope seemingly vanishing, a green light (Nemo) draws their attention to an underwater exit that leads them back to the sea and the arms of their companions.