In the city of Thujara in Shem, Conan becomes involved in a street brawl and injures Roganthus, the strong man of a traveling circus troupe.

A combination of regret over the troupe's loss and attraction for another member, the beautiful panther-trainer Sathilda, leads Conan to offer his own services as a stand-in for Roganthus.

Joining the troupe, he accompanies them first to the town of Senjaj and then across the river Styx to Stygia, where they hope to become wealthy performing in the capital of Luxor.

Luxor is ruled by a tyrannical emperor, Commodorus, who forces Conan's troupe to fight for their lives in his arena against exotic warriors and wild beasts.

The plot, seemingly building to a climactic final battle, is instead resolved by a catastrophic natural disaster, in the course of which Commodorus meets a fitting fate and much of Luxor is devastated.