I don't usually read stand alone books by authors whose series I read. The characters in the series are what keep me coming back. I love Tess Gerritsen's Rizzoli and Isles series (not the TV series, which couldn't be farther from the books). I thought, however, I'd try this one.
Julia Ansdell is a professional violinist. While on tour in Rome, she buys a piece of old, handwritten sheet music in an antiques shop. The proprietor can't tell her anything about the composer: L. Todesco.
Back home, Julia is practicing the piece, called Incendio, when her 3-year-old daughter, Lily suddenly stabs their old cat to death. The next time she's playing Incendio, Lily stabs her in the thigh. A nicely placed toy truck on the stairs causes her to fall. She's certain there's something evil in Lily and that Lily is trying to kill her. Julia's mother died in an insane asylum after she dropped her newborn and he died. Is this propensity for evil hereditary? Or does Incendio cause people to do evil things?
Julia and a friend go to Venice to try to find out more about the composer. While there, someone tries to kill Julia.
Playing With Fire alternates Julia's story and the story of Lorenzo Todesco, a young violinist in Venice during World War II. Lorenzo's story is more interesting than Julia's.
Tess Gerritsen, herself a musician (and physician), wrote the piece of music called Incendio. You can listen to it at a website she provides.