Spartacus continues to assemble a formidable army and outwit Rome's finest commanders. The desperate powers of Rome are forced to turn to the wealthy and ambitious Marcus Crassus to aid in the campaign against the rebellion.

Spartacus leads a daring assault to provide food and shelter for his people. Crassus builds a fearsome army and receives an unexpected visitor.

Spartacus considers striking a deal with a band of marauders to ensure his people stay supplied and fed. Crassus' son Tiberius makes a bold and fateful decision.

The possible infiltration of a Roman spy causes tension to mount between Spartacus and the men under his command. Crassus resurrects a long abandoned form of Roman punishment to teach his soldiers a brutal lesson.

Spartacus puts a plan in motion to weaken Crassus' forces and gain the upper hand. Betrayal threatens to foil the plan.

As Crassus leads an onslaught against the rebel-occupied city, Gannicus finds himself trapped behind enemy lines. Tiberius is tasked by Crassus to hold a celebration in honor of a man he despises.

Their forces pinned in on a snowbound, impassable ridge, Spartacus and Crixus come into conflict over the method of escape. Crassus discovers it increasingly difficult to control the actions of those closest to him.

Spartacus and the rebels arrive at a crossroads. With the relentless Crassus driving his men hard in the pursuit of Spartacus, the conflict between Tiberius and Caesar escalates.

Crassus learns that a fellow prominent Roman is attempting to steal the glory of defeating Spartacus he feels is rightfully his. Spartacus aims to secure a bargaining chip he can use against the Romans and celebrates the memory of a fallen brother.

Spartacus and his outnumbered rebels make one last attempt to win freedom in an epic final battle against the Romans led by Marcus Crassus.