A young Parisian couple are embarking on fertility treatment when the man, Antoine, becomes convinced he saw his sister in news footage from Syria. The same sister who supposedly died two years before. He makes a rash decision.

Three childhood friends from London, Iyad, Paul and Nasser enter the fray. Antoine finds himself in the middle of a fire fight and recalls the aftermath of Anna’s death. A dedicated Kurdish YPJ soldier, Sarya, is sent on a new mission.

Light is shed on what happened in Antoine’s family before Anna disappeared. In the present, Sarya gives Antoine weapons training and they begin to understand each other. ISIS mount a ferocious attack on a village.

Sarya’s past begins to come into focus as she finally lets her guard down with Antoine. The ISIS fighters seem to be on a roll and Nasser is rewarded with a high stakes introduction to ‘The Libyan’.

The mysterious Stanley turns up somewhere unexpected. More about Anna’s life after France is revealed.

Antoine makes a huge discovery and must make a crucial decision. Nasser, Paul and Iyad reach the capital of the Islamic State where Nasser does his best to protect his friends.

Antoine and Sarya’s unit get split up in the field. In the ISIS camp, Paul demands a reckoning. Stanley still has a few tricks up his sleeve.