When a rival club cleans out and then destroys their illegal arms warehouse, SAMCRO (Sons of Anarchy Motorcycle Club, Redwood Original) executes their own sense of justice in retrieving their guns. Meanwhile, family issues take center stage with a medical emergency involving Jax Teller's newborn son.

As the club deals with the aftermath of its illegal arms warehouse attack, the deputy chief of police poses a new threat to SAMCRO's reign over Charming; Jax continues to worry about his newborn son's fate; Opie faces a difficult decision.

When a prominent Charming family's young daughter is assaulted at a carnival, SAMCRO races against the authorities to capture the assailant; a new shipment of guns arrives from the group's IRA connection; Tara's ex-boyfriend arrives in Charming.

With the IRA gun payment looming, Samcro scrambles to come up with the cash; the Mayans and Nords take a drastic step toward strengthening their alliance; Jax finds himself in a dangerous position with Tara.

SAMCRO plans retaliation on a rival biker club while dealing with wounded Cameron Hayes in the clubhouse; Jax, Bobby and Opie try to end the gun debt for good.

Donna's death has the club divided, with Clay setting up a new gun deal with the IRA. Charming and SAMCRO 's hold on the city is threatened after Ethan Zobelle a sophisticated separatist opens a tobacco shop. Zobelle and his less-sophisticated associate are determined to take SAMCRO down due to their black and Latino bikers.

Zobelle comes up with a problem that Hale can solve to frustrate SAMCRO. Meanwhile, Gemma being raped is really affecting her relationship with Clay and the fact that Jax is involved with Luanne's porn business is bothering Tara. Clay decides to give Bobby the responsibility of running the business side of Luanne's.

Zoebelle incites Clay, who plans a course of retaliation, causing Jax to look to an unlikely source to keep the club from being destroyed. Tara learns from Gemma how an old lady handles anger.

When SAMCRO's adult-film business becomes a hindrance to the club, Clay seizes the opportunity to revive the gun-running cartel. As Jax and Clay continue to clash over club activities, their relationship reaches a new level of antagonism.

To protect their territory, SAMCRO must handle a rat at St. Thomas.

When SAMCRO pays a visit to another charter, not everyone’s happy to see the mother chapter.

The club embarks on a protection run, the likes of which they’ve never seen before.

An attack at the compound leads SOA to seek revenge.