Suspended in Language: Niels Bohr's Life, Discoveries, and the Century He Shaped (2004)

If you have ever drawn the little solar-system atom, this is the story of the man behind that model. Jim Ottaviani and Leland Purvis follow Niels Bohr through the discoveries that made him one of the founders of quantum physics and through a century his ideas helped shape. A nice extra is the footnotes, illustrated by guest artists including Jay Hosler, Roger Langridge and Linda Medley, which add a change of style and voice to the main story. It asks a little more of the reader than Feynman does, so it makes a good second book once that one has you curious about the quantum world.