Bubblegum psychology

the long version

Brenna Goldsmith is a person who generally keeps her thoughts to herself. When she is caught with arson on her hands, she is sent to a local sanatorium, excited to find that here she has the opportunity to say whatever she wants. She is sent from doctor to doctor, feeding them fake stories and finding just the right thing to get them upset enough to transfer her. That is, until Dr. Cannon. Though Dr. Cannon doesn't seem anything special, he can always tell when Brenna is lying and abruptly brings and their psychology sessions to an end if she does. Interested by this, the girl starts telling the truth, unbelievable as it seems.