I bet you can't become the biggest selling female author in the World. Or, Agatha Christie's The Mysterious affair at Styles.

Agatha Christie apparently wrote The mysterious affair at Styles as the result of a bet.
The loser of this bet, Her Sister, thought  that Christie couldn't write a Crime Detective story that kept the reader guessing the identity of the Murderer until the end, despite knowing everything that the Detective knew throughout.
She not only lost the bet in a spectacular fashion but in the process kick started the career of the biggest selling Female author the world has known. Shakespeare beats Christie's 3 - 4 Billion estimated books sold, but he does have 300 years head start by dying in 1616. Christie wrote "Styles" in 1916.

Originally serialised in the London Times Newspapers Colonial edition, The Weekly Times, from February 27  to June 26, 1920, the book edition was first published in October of that year, in New York, by John Lane. The UK Edition followed on 1st February 1921, published in London by The Bodley Head.

This attractively designed book, with its architectural design stamped in black to the spine and front board of the publishers brown cloth binding, introduced one of the most popular and enduring characters in the Genre. Hurcule Poirot, the dapper Belgian detective with a head "exactly the shape of an egg" was to appear in another 32 novels as well as 54 short stories, alongside his colleagues Lieutenant Hastings (the narrator of Mysterious Affair at Styles), and Inspector Japp of Scotland Yard.

The combination of being the Author's first book, the introduction of one of the most popular fictional characters of the 20th century, and a great read as well, have made The Mysterious Affair at Styles a much sought after book in First Edition, with copies of the London Bodley Head edition most prized by collectors . Copies in fine condition are scarce on the market. Copies in the original Alfred J Dewey illustrated dustwrapper don't turn up at all.

So, ninety years after the appearence of her first book, Agatha Christie maintains not only her place in readers affections as one of the most popular writers, but also in the Guinness book of World Records as the biggest selling novelist.

Regular broadcasts of Radio, Film and Television adaptations, including the hugely popular portrayal of Poirot by David Suchet, as well as translations of the books into over 100 languages are sure to keep her there for a long time and must even make J. K. Rowling envious.