The mysterious affair at styles is a detective novel by british writer agatha christieit was written in the middle of the first world war in 1916 and first published by john lane in the united states in october 1920 and in the united kingdom by the bodley head john lanes uk company on 21 january 1921 styles was christies first published novel it introduced hercule poirot inspector . The mysterious affair at styles tv 14 1h 43min crime drama mystery episode aired 16 september 1990 season 3 episode 1 previous all episodes 70 next hastings renews his friendship with poirot and involves him in the mysterious poisoning of the mistress of a manor house married to a man twenty years her junior. The mysterious affair at styles agatha christies first novel the mysterious affair at styles was the result of a dare from her sister madge who challenged her to write a story the story begins when hastings is sent back to england from the first world war due to injury and is invited to spend his sick leave at the beautiful styles court by his old friend john cavendish. The mysterious affair at styles is a detective novel by agatha christie it was written in 1916 and was first published by john lane in the united states in october 1920 and in the united kingdom by the bodley head john lanes uk company on 21 january 1921