The Endeavor's crew is ordered to determine if the wreck of a 18th Century galleon proves that the Spanish discovered Australia before Captain Cook.

The Minus Five team discover a murdered man in Barrier Reef waters, and he is buried on a small, lonely island. He is to be exhumed by the police, but when Sgt. Davies goes to the grave the body is missing, and the Minus Five team land in a strange network of intrigue.