After a Thracian warrior rebels against a former Roman ally, he and his wife are captured and sold as slaves.
Her fate is uncertain, but his punishment is to die in battle in the gladiatorial arena.
Following his surprising survival at the games, the newly christened Spartacus arrives at the ludus of Batiatus, where his new master promises to reunite him with his wife Sura, as long as he trains as a gladiator.
Though Spartacus proved himself during training and now wears the attire of a gladiator, his coarse attitude and relentless quest to see his wife isolates him from his fellow gladiators and Doctore.
Having performed shamefully in the arena against Crixus, Spartacus is forced to fight in the Pits. Batiatus, determined to profit from Spartacus, may be at risk if his debts aren't repaid.
Bitter enemies Spartacus and Crixus are charged with learning to fight as a team in order to take on an unbeaten champion in the arena. Meanwhile, a financially strapped Batiatus receives an opportunity of a lifetime that involved his battling band of gladiators.
Lies, distrust and duplicity plague the house of Batiatus and impact the hopes of both Barca and Spartacus, who have benefited from good fortune and envision a future away from the grounds. Barca expects to buy his and his male lover's way out, while Spartacus anticipates his promised reunion with his enslaved wife, part of his reward for a monumental victory in the arena. But just in case things go wrong, Spartacus dreams and schemes an escape plan.
Overcome by the pressure of Batiatus's control, Spartacus must make a choice: leave his past behind and assume the mantle of a champion gladiator, or die.
Batiatus purchases a fresh batch of slaves during an auction to be trained as gladiators and ponders the idea of selling Crixus.
Batiatus breaks the news that Spartacus is to service the richest woman in Rome.
Spartacus and Crixus are set up to fight in an exhibition match for Numerius' birthday - but Crixus is intent on blood.
Spartacus hovers on the brink. Meanwhile, Batiatus plots revenge against his enemies.
Lucretia and Batiatus anticipate the arrival of Glaber; Spartacus has a plan for revenge.
Spartacus convinces Crixus and the other gladiators that they could easily overpower the ludus guards and gain their freedom, and vows to kill Batiatus, as revenge for his wife's death.
Spartacus discovers the grave responsibilities and costs involved in his new role as a leader of freed slaves. Claudius Glaber’s arrival in Capua forces Spartacus to keep his rebellious band intact.
Spartacus and his men liberate a Roman villa, but its slaves are wary. Oenomaus throws himself into the brutal Pits, and Glaber supports Lucretia’s prophecies, despite Ilithyia’s protests.
After learning of Naevia's fate, Spartacus must deal with a rift among the gladiators; Lucretia divulges a long-kept secret in order to strengthen her position; and the rebels find themselves at risk after an attack.
Spartacus leads survivors through the woods, but Crixus gets separated and returns to a place of past suffering. Lucretia pries into Ilithyia’s affairs, seeking influence with a powerful Roman.
Spartacus leads a bold mission to free Crixus from Roman captivity, but a storied gladiator from the House of Batiatus complicates matters. Ilithyia’s scheming puts her marriage to Glaber at risk.
Spartacus rallies the rebels to begin training in order to be ready to defend their new sanctuary, while Glaber welcomes powerful new recruits to his forces.
Spartacus and the rebels look to increase the size of their force by freeing and recruiting fighters held as slaves during foreign wars; Lucretia recruits one of her husband's ex-gladiators in an attempt to outmaneuver influential Romans.
Spartacus contemplates an opportunity for revenge after the capture of an influential Roman; intrigue is at a fever pitch among Glaber and the women in his circle.
Spartacus must convince his people to unite against the imminent Roman assault. Lucretia struggles to be free from the commands of men who threaten her fate, and Glaber’s ruthlessness has consequences.
When dwindling supplies threaten to bring the rebellion to its knees, Spartacus tries to restore hope among his people.