Throughout December 1767, Alistair Douglas has been using the Decipherers' network of contacts in London to attempt to find two men, Pearce and Flanagan, who have been tracked to London from Boston - well-known as dangerous men and natural leaders of the mob. As rumours fly around, there have been an increasing number of anonymous printed attacks on the King and his ministers. But, frustratingly, there are few leads. Douglas is therefore pleased when he is assigned to a new duty; to travel to Paris and ensure that the outlawed radical writer and politician John Wilkes returns to England - the stipulation being that Wilkes must return of his own volition. It soon becomes clear that there is a serious conspiracy afoot - and John Wilkes is first on the list of suspects. But the Decipherers also have reason to believe that there is a London-based intimate of the present government also involved. As a pleasant posting turns into a web of conspiracies, Douglas must work out how to deal with Wilkes, so that the more dangerous co-conspirator can be flushed out, and the conspiracy then crushed . . .