Is this plot too overused?

It's about a 17-year old girl named Melanie Rae Adkins. When she was maybe five years old, she was found in an alley unconscious, burnt badly, and drenched with her own blood. At the hospital, everyone thought for certain that she wasn't going to make it by morning, but the next day she was awake, breathing normally, and able to make coherent conversation. When asked about her parents, she couldn't remember anything about them or her life before she was found. After months of searching for anyone who knew the girl and no results, they put her in a adoption agency, where she is adopted two years later by Joe and Jennifer Adkins. The whole book is basically about her trying to find her parents and how she survived while the people who tried to kill her when she was five find out about her survival and are determined to finish the job. But as Melanie's adventure leads her to Italy, she begins to discover that the closer she gets to uncovering the secret of her family and survival, whoever is chasing after her is growing stronger - in ways that shouldn't be humanely possible - as her possibility of surviving this adventure becomes less and less certain.