The police launch an investigation to find the bombers, whose skill and sophistication keeps them one step ahead. Under pressure to get results, Helen makes a breakthrough.

Lana breaks protocol to try to help Alex, knowing he has nobody else to turn to. Then the team makes a shock discovery about the terror cell they’re tracking down.

Lana is faced with an impossible decision when she is kidnapped by the terror cell. A choice between her duty and saving those who matter the most to her.

As the team mourns Thom's death, a new lead emerges - an informant, promising intelligence on the terror cell. Meanwhile a journalist is sent a suspicious package.

Counter Terrorism Command learn more about the recent murders with the help of Lana, but their progress doesn't go unnoticed by the bomber as their campaign deepens.

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?

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.

As the bombing campaign intensifies, so do inter-community tensions as the far-right group English Flag take to the streets to blame Islamists for the attack.

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.