Darwin
Got the latest Terry Pratchett "Science of Discworld" book in the mail, and the primary subject is evolution. Highly recommended! Some of the science in the non-fiction interludes was a bit deep for me, especially some of the high level physics and math, but all of it is good and I learned several things I hadn't known before about biology.
Can't let Darwin go by without also recommending a delightful, little-known, and surprisingly educational comic book on him by Jay Hosler, who is also the author of "Clan Apis."