The Secret Adversary: A Tommy and Tuppence Mystery (Warbler Classics), Paperback

The Secret Adversary introduces Tommy Beresford and Tuppence Cowley, two young friends who form Young Adventurers Ltd. and advertise themselves as "willing to do anything. Go anywhere...no reasonable offer refused." They were the characters Christie most enjoyed. Includes a detailed biographical note and a brief history of the Lusitania.