Double Cross: The True Story of the D-Day Spies by Ben Macintyre, 399 pages

Everything I've read (or listened to) by Ben Macintyre have been very readable non-fiction books about British spies or World War II.

I don't know if the subject is just intriguing to me, or if he just knows how to tell a great story, but he always makes history come alive in his accounts.

In "Double Cross" he tells the story of the spies, and their spy masters, who double crossed Germany and helped the Allies make the Normandy landings on D-Day a success.  What a time and what a story!