July 1940. As Britain braces itself for invasion, ex-Tommy and safecracker Bill O'Hagan is glad to have escaped the battlefield. But when a job goes wrong, he finds himself forced to serve his country once more. Spurned by his government and fearing for his life, the Duke of Windsor flees to Portugal with the woman for whom he abdicated the throne, Wallis Simpson. As a web of Nazi trickery threatens to ensnare him, his fate and the fate of Britain...