Lytcham Close, among the oldest stately homes in England, is owned with the last remaining heir and ruled by his intolerable whims. Old Hubert demands complete silence when he has music and situations dinner exactly by a resounding gong. Hurrying down at the sound of the second-or could it be the first?-gong, Joan Ashby is going to find out that not only is supper delayed, but something is going on that no-one can explain. Everyone is thrown into disarray when Old Hubert under no circumstances materializes and instead a new guest can be announced: Hercule Poirot himself. What unfolds is a secret of lovers, and a loss of life that is not as it shows up.