I believe Jeffery Toobin's "The Nine: Inside the Secret World of the Supreme Court" is a must read anyone that enjoys politics, law, or history. I haven't come across any book that captures the spirit of the Supreme Court and explains how today's court came to exist. The characters, background, and reasoning why each of the members were selected -- and their impact while serving.
The author describes how conservatives, angry with judicial setback after setback, systematically worked to stack the court and position key cases in parallel with their right leaning doctrine.
I was recommended this book by a very conservative friend. While I tend to lean to the left, we both felt this was evenly told.