Greenmantle by John Buchan

Catchy, readable World War One-era spy novel that really gives you a flavor of the international intrigues of the period. Takes the reader through various countries in Europe, ending up in Istanbul, as the characters try to prevent Germany from bringing the Islamic world onto their side. As such the book foreshadows one of the great global demographic and socioeconomic conflicts the world is facing now, and it reminds me for the millionth time how much history rhymes.

There are a few outlandish coincidences and meetings in the story, some of which are necessary to move the plot along. It reminds me of how Charles Dickens would do this--and just like Dickens, this author pretty much gets away with it! We chuckle to ourselves, enjoy the story in spite of the devices, and keep right on reading. 

Finally, there's a really well-done (and surprisingly affecting) scene at the end of the novel where the main characters, right when things look the bleakest, each express gratitude for their lives and for the various experiences they've had. It's a transporting scene. All in all this was a good read, a spy novel from a completely different era.