 Robert Barnard wrote "It is usually said that Christie drags herself into the modern world in the 'fifties, but the books in the late 'thirties show her dipping a not-too-confident toe into the ideological conflicts of the pre-war years.Here we have political 'idealists', fascist movements and conservative financiers who maintain world stability.But behind it all is a fairly conventional murder mystery, beguilingly and cunningly sustained."