Mrs McGinty's Dead is a work of detective fiction by British writer Agatha Christie, first published in the US by Dodd, Mead and Company in February 1952[1] and in the UK by the Collins Crime Club on 3 March the same year.

Poirot's misery in the run-down guesthouse, Mrs Oliver's observations on the life of a detective novelist and her growing frustration at artistic liberties taken during adaptions of her characters into plays, provide considerable entertainment in the early part of the novel.

The publication of Mrs McGinty's Dead may be considered as marking the start of Poirot's final phase, in which Ariadne Oliver plays a large part.

Superintendent Spence visits Poirot to ask him to find evidence that would forestall the execution of James Bentley, who has recently been convicted of killing his elderly landlady, Mrs McGinty, for a meager £30.

During the course of his investigations, Poirot discovers that, three days before the murder, Mrs McGinty took a clipping from a notorious Sunday newspaper, containing an article showing photos of females who had disappeared after being involved in decades-old criminal cases.

Poirot and Spence, using the ages of people in the town, conclude that someone is either Lily Gamboll, who committed murder with a meat cleaver at only 12 years old, or Eva Kane, a governess who had had an affair with her employer, Mr Craig.

In an attempt to flush out the murderer, Poirot claims to know more than he does, and is nearly pushed under an oncoming train, proving that the guilty party is still at large.

Having acquired originals of the photos used in the article, Poirot shows them to the villagers at a gathering at wealthy Mrs Laura Upward's house.

Recognizing the handwriting, Poirot gathers the suspects together and abruptly accuses Robin Upward of the murders, startling him into a confession.

Too proud to be pitied as a childless widow, Mrs Upward took in impoverished young men to take Robin's place, although she treated them more as a patron would a protégé, and dropped them if they turned out less than satisfactory.

Spence discovers that Shelagh Rendell has been receiving poison pen letters claiming her husband murdered his first wife.

Maurice Richardson of The Observer of 23 March 1952 thought that Poirot was "slightly subdued" and summed up "Not one of A.C's best-constructed jobs, yet far more readable than most other people's.

Death by Drowning in The Thirteen Problems and the excellent London working-class woman in The Hollow), but after a time it moves toward the better-spoken classes.

Poirot suffers in a vividly awful country guesthouse in order to get in with the community and rescue a rather unsatisfactory young man from the gallows.

However, in an unusual move, the character of Poirot was replaced with Miss Marple (portrayed by Margaret Rutherford), who comes onto the case when she is a juror in the trial of the lodger who is accused of the murder.

The adaptation is reasonably faithful to the novel, with the deletion of a few characters and omitting two of the women from the newspaper article – only focusing on Lily Gamboll and Eva Kane.

Thus it is Maude Williams, the estate agents' secretary (with dark hair instead of blonde), who is in love with Bentley and helps Poirot throughout his investigation.

In the US, the novel was serialised in the Chicago Tribune in its Sunday edition in thirteen parts from 7 October to 30 December 1951 under the title of Blood Will Tell.