July 1806. Commanding a prison hulk full of French captives, Lieutenant Martin Jerrold thinks his war can't get much better. He's far away from the more life threatening aspects of naval service and he can keep his mistress close to hand. It all seems too good to last.
And so it proves. When one of the prisoners goes missing, Jerrold's comfortable world is suddenly turned upside down. Ordered by the First Lord of the Admiralty to recapture the Frenchman at any cost, he finds himself racing across England: from the stinking marshes of Chatham to the wilds of Dartmoor and the fashionable resort of Brighton.
But what makes this prisoner so damned important? At the Post Office, Jerrold's old friend Mr Nevell is curious; so too are politicians from either side, including the cunning Tory leader Spencer Perceval. Even the seductive Princess Caroline takes an unexpected interest.
As Jerrold - dogged by his usual bad timing, bad luck and bad behaviour - closes in on his elusive quarry, he uncovers a devilish web of treachery and deceit stretching back twenty years and ensnaring the most exalted members of society. And in hot pursuit are those who will stop at nothing to stop him...