07:45am. A monk lies dead in Snowdonia, a knife protruding from his throat. The mission has begun.

08:56am. A London Underground train is stationary in a tunnel, four hundred passengers trapped inside.

09:15am. DCI Ed Mallory has just started his day. The Met's top hostage negotiator - despite having been blinded thirteen years earlier - Mallory is about to discover that, today, an underground train is not the only thing on the line.