Mademoiselle Deluzy-Desportes once was governess to the four children of the Duc de Praslin ( Charles Boyer ) and his wife, the Duchesse de Praslin ( Barbara O ' Neil ) in the last years of the Orleans monarchy in Paris.

Poirot suspects the truth, but can substantiate it only after contacting Zélie Meauhourat, the governess employed by the Ravenscrofts at the time of their death.

* Zélie Meauhourat, a governess to the Ravenscrofts