Roderick Alleyn, his wife and son are en route for a holiday in the Alpes Maritimes, combining business with pleasure On the night train, he saw something being killed as they flashed by the cliff-like wall of the Chateau d'Argent Just then, Miss Truebody, an English spinster further down the train, burst her appendix, and what followed was the most unconventional and fantastic few days that Alleyn and Troy ever endured in the cause of proving that English policemen are wonderful