Paganini's Ghost

Paganini -- showman, womanizer, virtuoso -- is one of the most charismatic characters in the history of classical music. His violin, il Cannone, is kept in Genoa, Italy, and played only once every two years in a sold-out concert by the winner of an international competition. But this year, a Parisian art dealer is found dead in his hotel room the day after the concert. In his wallet is a scrap of sheet music belonging to the competition winner. How did he get? And why?