Following the 2nd battle of Ypres, furious fighting continued on all fronts. Casualties were high, conditions dreadful, and life expectancy short. The only break the men had was a brief home leave, or a few days away from the trenches. It was no comfort, either, that many people back at home had little idea of the suffering in the battlefields, although concern was growing as the mounting casualty lists were published.
The first message sent to Tom Thorne's phone was just a picture - the blurred image of a man's face, but Thorne had seen enough dead bodies to know that the man was no longer alive. But who was he? Who sent the photograph? And why? While the technical experts attempt to trace the sender, Thorne searches the bulletins for a reported death that matches the photograph. Then another picture arrives.