Bomb disposal officers Lana Washington and Joel Nutkins are called out to a Met counter-terrorism operation at a London housing estate to investigate a potential bomb factory and suspected bomb-maker Andy Phelan.

A far-right group called the Crusaders claim responsibility for the mosque attack. Lana finds a forensic link between the bomb at the mosque and the one at Westhaven - were they both bombed by the same person?

Following the murder of a Counter Terrorism officer, Lana Washington and the EXPO team race against time to stop the bombers before they strike again.

Lana struggles to come to terms with her personal loss, and her failure to prevent the explosion. Meanwhile, Counter Terrorism officers identify the bomber and launch a massive manhunt.

The EXPO team are stretched to breaking point dealing with a complicated device planted at the Campaign HQ of the Progressive Alliance. Lana tells Karl she wants to break up.