‘How can a man disappear from a locked bathroom on a plane in mid-flight? That’s the mind-bending puzzle at the heart of… Vailati’s stellar mystery… Golden Age fans will be delighted by the baffling crime and the logical and plausible solution.’ Publishers Weekly

As the principal investigator explains, there seem to be four alternative explanations: accident, suicide, murder and purposeful escape, each of which he demonstrates convincingly to have been impossible! After one ingenious theory is disproved, the eventual stunning explanation is revealed.