In an age of treachery everyone must pick a side…

Newly returned from years of secret work in Paris, Lieutenant Holcroft Blood, a brilliant but unusual gunnery officer in His Majesty's Ordnance, must now face King James II's enemies on the gore-drenched battlefields of the British Isles.

But after the victory at Sedgemoor - and its cruel aftermath, the Bloody Assizes, in which the Duke of Monmouth's rebellion was ruthlessly crushed - many powerful men have grown tired of Catholic James's brutal, autocratic rule and seek to invite William, the Protestant Prince of Orange, to seize the thrones of the Three Kingdoms.

While revolution brews in the gentlemen's clubs of London, Holcroft discovers that a sinister French agent, known only by his code name Narrey, has followed him across the Channel and intends to murder him. Worse, Holcroft must decide whether to join the conspirators, including his old friend Jack Churchill, now Lord Marlborough, and support Dutch William's invasion - or remain loyal to his unpopular king.