The Girl in the Castle

Beloved #1 bestselling author James Patterson delivers a thrilling novel about a teen caught between two worlds and the truths that could set her free—or trap her forever

My name is Hannah Dory and I need you to believe me
 
Hannah Doe is brought to Belman Psych, kicking and screaming, told she is suffering from hallucinations and delusions.
 
1347: Hannah Dory and her village are starving to death in a brutal winter. Hannah seeks out food and salvation in the baron's castle. If she is caught stealing, she will surely hang.
 
Hannah knows the she is Hannah Doe and Hannah Dory, and she must return to the past before it's too late to save her sister. Can Jordan, the Abnormal-Psych student who seems to truly care, be the one to finally help her?

Jordan isn't sure what to believe, and Hannah has even bigger if she doesn't make it back, her sister will die, but if she keeps going back, she might never escape.