There’s something fishy about the fish paste sandwiches that wealthy heiress Elinor Carlisle offers her guests at an impromptu picnic.

They’re laced with deadly morphine hydrochloride and before lunch is over, the youngest picnicker, beautiful Mary Gerrard is dead.

It’s too much of a coincidence – Elinor’s fiancé Roddy has recently broken off their long-standing engagement to pursue Mary, a protégé of Elinor’s recently deceased aunt.

And there are rumours too that aunt Laura, also a victim of poisoning, had planned to leave a substantial share of her fortune to the girl. 

Almost everyone, including Roddy, who has known Elinor since childhood, believes she must be guilty. Can Hercule Poirot find out the truth?

Of course, he can.

Agatha Christie’s Belgian detective is in sparkling form in Sad Cypress, first published in 1933 and the first in the Poirot series to be set partially in a courtroom.

But the big mystery is not whodunit but whether Elinor can forgive Roddy’s brief infatuation or will she find happiness with the local doctor, who has believed in her innocence throughout?

For my money one of the finest books in the Christie canon: the queen of detective fiction spends a fair bit of time establishing the characters and the plot and Poirot doesn’t make an appearance until almost halfway through.

But it doesn’t matter: the red herrings have an authentic smell and the clues are deftly interwoven.

Don’t blame Christie if you want to kick yourself when the murderer is revealed.

• Several sources list the date of publication as 1940 but my 1979 Pan edition, lists the publication date of the original William Collins edition as 1933.

Review by Sue Featherstone

Sad Cypress is available to buy on Amazon.