For fans of espionage in general, or Eric Ambler in particular, this may be of interest. The earliest of his novels, it shows the skills he would finely hone in later works (e.g., The Mask of Dimitrios, Epitaph for a Spy, State of Siege) as well as some youthful exuberance he would prune from later writing (a bit too much "in the nick of time" heroism). Aside from the plot, which can readily be found online, the noteworthy aspect of this novel is a dramatic shift in point of view halfway through, something I cannot remember encountering in other novels, certainly none of Ambler's. It is forecast by an equally surprising change in the protagonist's name (from Barstow, a British professor of physics, to Conway Carruthers, Our Intrepid Hero), which seems triggered by a car crash. This alter ego, whom Barstow seems to willingly choose (though why isn't clear at the time), creates a bit of confusion. Is this real? Is Barstow dreaming everything that happens after the crash? (The explanation isn't resolved until the epilogue). The POV change happens midway and is marked as such, which makes the reader see Barstow/Carruthers from inside and outside, thus questioning whether the protagonist's derring-do and Bond-like equanimity is as much hero-worship by the second major character (Casey, the American journalist) as it is self-delusion or genuine self-discovery of hitherto unknown depths of courage and resourcefulness. In fact, one wonders if Ambler wasn't consciously spoofing the Bulldog Drummond-like fictional heroes of the time. As a lifelong fan of Ambler, who enjoyed this as an example of the artist as a young man (he he was 27 at the time), I would advise that if you have heard of him and want to know what he was about ("Did John le Carré really say Ambler was 'the source on which we all draw'?"), start with Mask of Dimitrios or Epitaph for a Spy, not here.