** spoiler alert ** 
 While I prefer the other Ambler book I've read to this one (Journey into Fear), this is still a good read with an academic protagonist and great locations, but it lagged a bit in the middle for me until Dimitrios went from theoretical to flesh and blood. Then it was really cloak & dagger and moved more quickly for me. 
 Still, well written, and the narrator, Alexander Spencer, does a solid job.