The trio are charged with escorting a valuable cargo across the desert, travelling into the unknown with a ramshackle caravan of strangers - and Pythagoras's feisty younger brother Arcas, who has joined them for the trip. The mission soon takes a decidedly spooky turn when they spend the night in a temple, where it becomes clear one of the travellers has something to hide. As danger closes in and a dark secret is exposed, the heroes are left fighting for their lives under the scorching desert sun.