As Hercule Poirot sifts through his post one particular morning, he alights upon a letter from an elderly and (as it transpires), exceedingly rich spinster Miss Emily Arundell. She is clearly in great distress and seeking his help, but doesnt say why. Her only specific mention is the incident of the dogs ball. However, what intrigues Poirot is the date of the communication it was written two months ago. He persuades Captain Hastings that they must visit the lady with all haste.

On arrival they discover that she has died, apparently of natural causes. But Bob, Miss Arundells devoted wire-haired terrier, knows better. And so, soon, does Poirot.

John Moffatt, as ever, stars as Hercule Poirot and Simon Williams as Captain Hastings.

With music specially composed by Tom Smail.

Full cast Radio 4 dramatisation

Agatha Christie, crime, Thriller