Same problems, different day. Spartacus needs to feed the army he's leading and it turns out that the pirates have mostly only been able to find wine. Which is delicious, but not helpful in feeding hungry soldiers. Meanwhile, people still want to get inside the city to trade with the rebels and the stipulation stands: no weapons, and show a mark that you were once a slave, and THEN you can enter. When Caesar shows up, he pretends to be a former slave and they let him in but don't entirely trust his story.
Also of note: that guy Nemetes, with the beard? Is taking money from the people entering the city, unbeknownst to Spartacus.
Meanwhile, in the Roman camp, Tiberius is getting bandaged up when his father Crassus shows up. There will be punishments for the foolish attempts against Spartacus. In the rebel camp, Spartacus and his officers talk about the dangers of having a spy in their midst. Little do they know, they already do! But Crixus is angry because he's built to fight, and Agron is chummy because he's also built to fight but also super loyal. Do we sense a problem in the ranks?
When Agron fights Caesar, he realizes that Caesar, who's masquerading as a slave, is a formidable fighter, and everyone takes an interest in him. Meanwhile Spartacus stops by and checks in with a defiant Laeta, who says that Crassus is sneaky and dedicated. Crassus, meanwhile, yells at Tiberius and tells him that the punishment for his rashness is decimation, which means five dudes are going to be killed at random – and among them could be Sabinus, Tiberius's not-boyfriend.
Meanwhile, at the whorehouse in New Spartacustown, Caesar and that no-good Nemetes say some racist stuff about pirates and how much they don't like Spartacus, while outside Laeta bumps into Sybil, who sees that she has bread. Then, when Gannicus goes outside to find Cassius being beaten by Brictius, Cassius asks if anyone's seen his sister. It doesn't sound like much, but wait for it – this gets gross. Meanwhile, Sybil tips off Gannicus about Laeta's bread.
Crixus and Naevia storm the whorehouse and ask Nemetes why he trusts Caesar. The fight doesn't really go anywhere but then some untoward stuff goes down. Caesar is taken to a back room where he meets a blond lady (the sister that Cassius was asking about). Turns out, Nemetes has seemingly been fueling a rebellion against Spartacus that started because Nemetes takes money at the gate. So the whole thing is a sham. Fabia, the girl, asks Caesar to kill her. And he does.
In the Roman camp, Crassus tells the soldiers that 10% of them will be killed and the rest of them will go live among whores and slaves. And then a surprise, Tiberius is to be cast among his men and punished as one of them. Sabinus draws a white stone, which means death. Uh-oh.
Meanwhile, in the rebel camp, Gannicus confronts Naevia after he learns that Attius had nothing to do with the disappearing Romans. There's a terrible fight and Naevia hits Gannicus in the head with a rock, and then Crixus uncharacteristically decrees that all the Romans should be killed, which Spartacus puts a stop to. In the Roman camp, Tiberius starts to kill his not-boyfriend and there are slaughters in both the Spartacus and Roman camp. A bloody night all around.
Finally, at the end of all the fighting, Tiberius tells his father he's learned his lesson, Crixus and Naevia wonder if they shouldn't go off on their own, and Caesar is thrilled with what he's done: created dissention in the ranks.