Winter, 1666. A second war has broken out between the English and the Dutch . . . Captain Matthew Quinton's fifth mission for King and country is to the Swedish court at Gothenburg. Sweden is at the height of its military power, and Quinton is charged with securing crucial support in England's new war against her old enemy, the Dutch republic. Accompanying him is the mysterious Lord Conisborough, who - unknown to his captain - is sworn to another, secret mission involving the notorious regicide John Bale, alone among peers of the realm to sign the death warrant of Charles I. Gothenburg proves to be a hotbed of dangerously conflicting loyalties, and Quinton and crew find themselves needing help from the most unexpected quarters.