Jessica Prince and the Crimson Caper

"Jessica Prince, the sixteen-year-old niece of billionaire businessman Henry Prince, goes with her uncle to Milan to see Carla Valentine, an old flame of Henry's and a popular new fashion designer. But the night of the show, the lead model is hurt, the lights go out, and a threatening note is left behind. Worst of all, Jessica sees a person in a red trench coat called the Crimson Caper who seems to be out to destroy Carla's Life if she won't quit fashion. With only her trusty notebook and love of mystery novels, Jessica sets out to solve the crime.
But as she delves deeper, she realizes there's more going on beneath the surface and she can't trust anyone. When Uncle Henry is framed and arrested for the sabotage, Jessica must rely on her intuition and observational skills before she loses her uncle forever."