The rebellious Thracian Spartacus, born and raised a slave, is sold to Gladiator trainer Batiatus. After weeks of being trained to kill for the arena, Spartacus turns on his owners and leads the other slaves in rebellion. As the rebels move from town to town, their numbers swell as escaped slaves join their ranks. Under the leadership of Spartacus, they make their way to southern Italy, where they will cross the sea and return to their homes.

Joe Mason suffers from amnesia and is often in trouble. Catherine Foster befriends him and they marry. After a jolt jogs his memory, he remembers that he is the son of a rich businessman from Chicago, but he can't remember anything recent.