A secret weapon. A traitor in plain sight. A hidden code.

England, 1940: Farmer John Cook finds his train stopped at gunpoint by men posing as Home Guard officers. As Cook confronts them, two men escape into the surrounding trees, carrying mysterious suitcases.

Lady Margaret is tasked with deploying Land Girls to local farms to aid the war effort. But when one of the new recruits is found dead in the woods, Margaret questions if there is a traitor in their midst...

Cook and Margaret investigate the murder and try to trace the men from the train. They soon begin to connect events with refugee scientists from occupied Europe at work on secret plans to create a weapon to end the war...

Cook and Margaret fight to turn the tide of the war. But can they trust anyone? Or even each other?

Everyone is gripped by Stephen Ronson:

'WWII set thriller that has heart-pounding action, but more importantly, a lot of heart... Completely gripping... A narrative that is as taut as piano wire!... Not to be missed if you enjoy action-packed historical thrillers' Reader review

'A gripping World War Two thriller... Every shadow hides a potential threat and the tension never lets up. A must read' Reader review

'Like watching a film... SO realistic! The attention to detail to historical fact is wonderful... Unputdownable page turner!' Reader review

'Read the book in three days, couldn't put it down. If you like wartime stories then this is a must read' Reader review