SO. GOOD. As an engineer, I found this book to be fascinating. It's basically a narrative about several skunk works projects like the U-2 and F117 interspersed with tons of insane and interesting side stories by people involved (mostly test pilots).
Here's one example. One engineer was formulating a new fuel for the U-2 that would work in the high altitude engine. The fuel was called LF something or other, and there was a running joke that that stood for "Lighter Fluid" due to it's awful smell. Chemically it was actually more similar to one of the main ingredients in the bug spray "Flit", which was popular at the time. The year they put the (still very top-secret) U2 into service, there was an unexplained nationwide shortage of bug-spray.