The Secret Adversary: (Annotated Edition)

Reunited in 1919 London, demobilised soldier Tommy Beresford and nurse Prudence "Tuppence" Cowley, out of work and money, form the "The Young Adventurers, Ltd." planning to hiring themselves out as "adventurers ... w]illing to do anything, go anywhere ... n]o unreasonable offer refused." They are overheard by a Mr. Whittington who offers Tuppence a comfortable position, but he is shocked when she randomly gives her name as "Jane Finn", a name Tommy in turn had overheard him use and mentioned during the same conversation. Whittington believes Tuppence is blackmailing him and sends her away with some money. Convinced that they can get further money out of Whittington if they play their cards right, Tommy and Tuppence prepare to shadow him, only to discover that he has closed his office and disappeared without a trace. To find out why, they place an advertisement, asking for information regarding Jane Finn. One response is from a Mr. "Carter," whom Tommy recognises as a leading figure in a British intelligence agency and who provides the background to Jane Finn, all of which was earlier revealed to the reader in the book's prologue. Jane Finn was a passenger on the RMS Lusitania when it sank four years earlier in 1915. An American man, knowing he would not be on the lifeboats entrusted her with getting a secret, draft treaty to the American embassy in London, should she survive the sinking and be rescued. Since that time, neither Jane Finn nor the draft treaty have been found. At the same time, publication of the treaty's contents would compromise the current British government, potentially leading to a bolshevik coup. Tommy and Tuppence agree to work for Carter on an unofficial basis, with the aim of recovering the treaty and foiling the bolshevists and their puppet-master, an elusive though hands-on figure known as Mr. Brown who is said to have an exceptional capacity for blending in the background. Carter agrees to cover all their expenses as well as pay them a large sum in the hope that amateurs may succeed where intelligence services failed.