When Elliot's drug shipment is spiked, rocking the Gangs and causing hundreds of passings, the hunt is on for who is responsible.

Sean, Billy and Cornelius make a drastic attempt to reclaim London, while Luan tries to take revenge and Elliot seeks answers.

Tormented by questions about his past and the spiking, Elliot believes mystery man Zeek holds the key and is determined to find him.

With tensions between the gangs coming to boiling point, Luan decides he must take drastic action to protect his family; armed with a shocking plan, will Luan succeed in striking his enemies before they come for him?

Lale grapples with the consequences of Sean's betrayal; separated from her people, locked in a brutal battle of wits, she will do anything to ensure her survival; Lale is determined to come out on top.

Elliot is forced to fight for his reputation and his life; he finally confronts Zeek, but their explosive showdown triggers a shocking series of events and forces Elliot to question everything he thought he knew about the spiking and his past.

Elliot finds himself the most wanted man in London; with time running out, he has no option but to put his trust in a surprising ally in an attempt to find out how and why his past connects to the unfolding conspiracy.

As the series hurtles to a climax, the truth behind the spiking has far-reaching consequences for all the gangs; old foes re-emerge, once-solid alliances implode and new allegiances are forged as the gangs take revenge.