In 2014 the estate of Agatha Christie authorised Sophie Hannah to write new stories featuring Hercule Poirot. So far there are five instalments in the series:
- The Monogram Murders (2014)
- Closed Casket (2016)
- The Mystery of Three Quarters (2018)
- The Killings at Kingfisher Hill (2020)
- Hercule Poirot's Silent Night (2023)
All the novels focus on Poirot, assisted by Edward Catchpool from Scotland Yard, investigating murders.
Contains examples of:
- Ambiguously Gay: Edward Catchpool is uninterested in women, romance or marriage. He also never shows any interest in men. It's ambiguous if he's gay or ace.
- Canon Foreigner: Catchpool is the most notable original character, invented to take Hastings' place (since Hastings is in Argentina during the novels).
- Clear My Name: The Mystery of Three Quarters starts with people coming to complain to Poirot because they received letters, supposedly from him, accusing them of murder. All of them insist they aren't guilty of murder. Poirot knows he isn't guilty of writing the letters. He starts to investigate the death of Mr. Pandy to clear his name and find who the real murderer is.
- Death by Falling Over: Kingsbury dies this way in The Mystery of Three Quarters. He falls (or is pushed; it's ambiguous), hits his head, and dies soon after. Justified because he's eighty and he hit his head very hard on a sharp object.
- Frame-Up:
- In The Monogram Murders Samuel and Jennie pretend to conspire to frame Nancy for the murders.
- The Mystery of Three Quarters: Barnaby Pandy wasn't murdered. He really did die naturally, but one of his granddaughters decides to make it look like murder so she can frame her sister.
- The Great Depression: Hercule Poirot's Silent Night is set in 1931, and the Great Depression is mentioned in passing.
- Interquel: Hannah's new novels are set between 1929 and (thus far) 1931, placing them chronologically between The Mystery of the Blue Train (1928) and Peril at End House (1932) from Christie's original series.
- Mondegreen Gag: Played for drama in The Monogram Murders. Catchpool thinks he hears Stoakley say "some kid" and responds to what he heard. Stoakley actually said "Sam Kidd". When Poirot realises this it helps him track down Jennie.
- Murder-Suicide: In The Monogram Murders one of the victims murders the others then lets his co-conspirator murder him.
- Murder the Hypotenuse: The accused and actual killer in The Killings at Kingfisher Hill claims to have murdered her fiancé because she fell in love with his brother.
- Never the Obvious Suspect: Inverted in The Killings at Kingfisher Hill. The killer is the woman who was arrested for the murder and who everyone thought was guilty.
- Oddball in the Series: The Mystery of Three Quarters is unusual because it starts, not with a murder, but with Poirot being framed for accusing people of a murder. For half of the book Poirot is also unsure if there was any murder, as the victim is believed to have died naturally.
- The Roaring '20s: Unsurprisingly for Poirot novels. The Monogram Murders is set in 1929.
- Shipper on Deck: In The Monogram Murders Poirot matchmakes Dr. Flowerday and Margaret.
- Shout-Out:
- In The Monogram Murders one of Shakespeare's sonnets is carved on Patrick and Frances' grave. In the same book Dr. Flowerday references The Tempest.
- Closed Casket frequently references Shakespeare's King John. A line from the play helps Poirot solve the mystery.
- Little Key, the house in The Killings at Kingfisher Hill, is named after a quote by Charles Dickens.
- Your Days Are Numbered: In Hercule Poirot's Silent Night, both the house and its owner are doomed. The house is built on a cliff that's being eroded, meaning it will inevitably fall into the sea. The owner is dying of cancer.
