Murder in Retrospect

First published in the US in May 1942. In the UK was first published in January 1943 as Five Little Pigs. This copy was the first printing by Dell in 1977.

Hercule Poirot had never faced a problem as thorny as this one. He had to find out who savagely hates a man whose work the world loved. He had to prove the innocence of a woman already convinced of murder. He had to make sense of a collection of clues to point in every direction at once.
So fa, it was the kind of case Poirot was used to. But there was one added complication:
The crime had taken place sixteen years before - and to solve it Poirot had to go beyond the grave...