N or M?

In this exclusive authorized edition from the Queen of Mystery, set during the dark days of World War II, Tommy and Tuppence Beresford are put on the trail of a pair of Nazi spies who have murdered Britain's top agent.

World War II is raging, and while the RAF struggles to keep the Luftwaffe at bay, Britain faces a sinister threat from "the enemy within"--Nazis posing as ordinary citizens.

With pressure mounting, the intelligence service appoints two improbable spies, Tommy and Tuppence Beresford. Their mission: to seek out a man and a woman from among the colorful guests at Sans Souci, a seaside hotel. But this assignment is far from an easy stroll along the promenade--N and M have just murdered Britain's finest agent and no one can be trusted.

Agatha Christie is the most widely published author of all time, outsold only by the Bible and Shakespeare. Her books have sold more than a billion copies in English and another billion in a hundred foreign languages. She died in 1976, after a prolific career spanning six decades.