Hercule Poirot is determined to solve an old husband and wife double murder that is still an open verdict…Hercule Poirot stood on the cliff-top. Here, many years earlier, there had been a tragic accident. This was followed by the grisly discovery of two more bodies – a husband and wife – shot dead.

The bodies of General Alistair Ravenscroft and his wife Molly were found shot dead near their manor house in Overcliffe. Left behind are two orphaned children, including daughter Celia.
Ten years later, Mrs. Ariadne Oliver, godmother to Celia, is approached at a literary luncheon by Mrs. Burton-Cox, to whose adopted son Celia Ravenscroft is engaged and asked to investigate who had killed whom? Was it a suicide pact? A crime of passion? Or cold-blooded murder? Does Celia have bad blood?

Poirot delves back into the past and discovers that ‘old sin leave long shadows’.