Growing up in a New York City orphanage has given scrappy Amelia Matthew the pluck to survive in a rough time and place. Combining moxie with a modicum of psychic talent, she manages to earn enough to create a decent life for herself and her beloved foster brother, Jonas. When a knock on the head changes Amelia's mild ability into something far more powerful, she's shocked. As she grapples to understand her newfound skills, a strange vision in a public park assaults her. The next thing she knows, she's waking up in a city insane asylum on isolated Blackwell's Island. Despite her protests, Amelia is unable to leave. Even Jonas can't find a way to free her. 

In spite of himself, Andrew Cavanaugh, a young doctor from Philadelphia, finds himself quite taken with the pretty new patient. Naturally, he doesn't believe her when she claims to see spirits—until she proves it to him. As Andrew works to release Amelia from care, he's approached by a desperate mother searching for the daughter she believes is being hidden in the asylum. With Amelia's help, he looks into the case, uncovering a shocking trail of corruption and cruelty at his workplace. Powerful people rule the asylum. What can a lowly doctor and his imprisoned patient possibly do for their helpless victims? Especially when Amelia's dubious gift is still so uncontrollable and she's not entirely sure she doesn't belong on Blackwell's Island herself...