There are 78 books in the Hercule Poirot Mysteries series.
The Hercule Poirot Mysteries series does not have a new book coming out soon. The latest book, Curtain: Poirot's Last Case (Book 39), was published in September 1975.
The first book in the Hercule Poirot Mysteries series, The Mysterious Affair at Styles, was published in October 1920.
The Hercule Poirot Mysteries series primarily falls into the Mystery genre.