The Submarine Plans
Poirot is summoned to the home of Lord Alloway, the aspiring Prime Minister. Plans for England’s new submarine have been stolen from Alloway's household and Poirot is his only hope. From Poirot's Early Cases and The Under Dog and Other Stories.
More about this story
Later lengthened into the novella The Incredible Theft, the plans for a top-secret submarine are stolen during a party held by the head of the Ministry of Defence.
It first appeared in book form the US collection The Under Dog and Other Stories in 1951. It was not until 1974 that the story featured in a UK collection, Poirot’s Early Cases.
This story was not adapted for TV because Agatha Christie’s rewritten version, The Incredible Theft, featured in season one of Agatha Christie’s Poirot in 1989, starring David Suchet, and followed a similar plot and structure.