The Big Four

The atmosphere in King's Abbot is far from idyllic. Gossip, suicide, the death of the titular Roger Ackroyd... Hercule Poirot engages in a game with an exceptionally cunning murderer. The detective's assistant is Dr. Sheppard, the local doctor who knows the secrets of the small community very well. The novel sparked controversy because some of its plot elements were said to contradict the canons of detective literature at that time, leading Agatha Christie to be reportedly excluded from the club of authors of detective novels.