How do you stop an assassin you cannot see?

In this fast-moving thriller, Iona Khan – a young female detective with Manchester police – receives a tip-off about a coming terror attack.

With a major political conference about to take place, she must move quickly if multiple fatalities are to be prevented.

Normally, the city’s state-of-the-art CCTV network would be used to covertly monitor the bomb plotters’ movements. But in this case, the tactic proves futile: the gang have found a way to strike from beneath the ground…