A fifteenth-century painting by a Flemish master is about to be auctioned when Julia, a young art restorer, discovers a peculiar inscription hidden in a corner: Who killed the knight? In the painting, the Duke of Flanders and his knight are locked in a game of chess, and a dark lady lurks mysteriously in the background. Julia is determined to solve the five-hundred-year-old murder, but as she begins to look for clues, several of her friends in the...