Bombs detonate in a busy souk, causing massive devastation. An explosion rips apart a mosque, killing and injuring those inside. But this isn't the Middle East - this is Cardiff . . .

In a city where tensions are already running high, DC Will MacReady and his colleagues begin the desperate hunt for the attacker. If they knew the 'why', then surely they can find the 'who'? But that isn't so easy, and time is fast running out . . .

MacReady is still trying to prove himself after the horrific events of the previous year, which left his sergeant injured and his job in jeopardy, so he feels sidelined when he's asked to investigate a vicious knife attack on a young woman.

But all is not as it seems with his new case, and soon MacReady must put everything on the line in order to do what is right.