Superintendent Macdonald, C.I.D., studied his fellow-passengers on the Vienna plane simply because he couldn't help it, because he hadn't conditioned himself to being on holiday. The distinguished industrialist he recognised: the stout man he put down (quite mistakenly) as a traveller in whisky. The fair girl was going to a job (he was right there) and the aggressive young man in the camel coat might be something bookish. Macdonald turned away from his fellow-passengers deliberately: they weren't his business, he was on holiday—or so he thought.
Against the background of beautiful Vienna, with its enchanting palaces and gardens, its disenchanted back streets and derelicts of war, E. C. R. Lorac constructs a detective story with all its complexities; an exciting and puzzling new crime story.