Agatha Christie wrote The Mysterious Affair at Styles during the midst of World War I. The book was published in 1920 and became extremely popular because of the well-grounded plot and interesting characters. The novel is set at Styles Court, a wealthy estate in England during the war. The estate's owner, Mrs. Cavendish, had inherited the estate as well as vast sums of money from her late husband.

From the brilliant pen of Agatha Christie comes two novels featuring the beloved sleuthing duo: In the The Secret Adversary, Tommy and Tuppence decide to embark on a daring business scheme: Young Adventurers Ltd. But they get more than they bargained for when their first assignment for the sinister Mr. Whittington draws them into a diabolical conspiracy. Set during the dark days of World War II, Agatha Christie’s N or M? puts two most unlikely espionage agents, Tommy and Tuppence Beresford, on the trail of a pair of Nazi spies who have murdered Britain’s top agent.

Hercule Poirot's quiet supper in a London coffeehouse is interrupted when a young woman confides to him that she is about to be murdered. She is terrified - but begs Poirot not to find and punish her killer. Once she is dead, she insists, justice will have been done. Later that night, Poirot learns that three guests at a fashionable London Hotel have been murdered, and a cufflink has been placed in each one’s mouth. Could there be a connection with the frightened woman?

This mystery novel follows Anthony Cade, a man who unknowingly finds himself in the middle of an international conspiracy and a murder investigation after accepting a simple delivery job from an old friend. As Cade slowly begins to realize his predicament has potentially put him in danger, he begins his own investigation into the strange series of events just as Inspector Battle of Scotland Yard begins the main, official investigation.

Pretty, young Anne came to London looking for adventure. In fact, adventure comes looking for her - and finds her immediately at Hyde Park Corner tube station. Anne is present on the platform when a thin man, reeking of mothballs, loses his balance and is electrocuted on the rails. The Scotland Yard verdict is accidental death. But Anne is not satisfied. After all, who was the man in the brown suit who examined the body? And why did he race off, leaving a cryptic message behind?