The Queen’s Gambit is Diane A. S. Stuckart’s first Leonardo da Vinci mystery. It is told in first person by Dino, one of Leonardo’s apprentices. I won’t spoil the story by giving away Dino’s secret.
The novel was a little slow, but I did enjoy it and plan to read the sequels: Portrait of a Lady and Bolt from the Blue (due out in January 2010).
If you enjoy mysteries and historical fiction, I highly recommend it.