Les Diamants volés
Freeman Wills Crofts1924

Inspector French is the central figure in many books by Mr. Crofts. This, his greatest case, opens with the discovery beside the open safe of a diamond merchant in Hatton Garden of the dead body of his head clerk, and valuable diamonds are missing. There are many people to suspect, and before Inspector French solves it, he has to unravel many mysteries and follow up many false clues

Titre original : Inspector French's Greatest Case (1924)