When Didion Dumont wakes up in the hospital after a failed suicide attempt, she finds she was successful in one aspect: she will not be returning to the tatters of her former life.

While in a state psychiatric facility, she receives surprising news: she will be moved to Riverside Rehabilitation, a private psychiatric hospital in rural Iowa that takes on special cases like hers.

Didion can't believe the doctor at Riverside will find anything 'special' about the hallucinations she has suffered since childhood. But when she meets the other patients in the Green Ward, it is clear that something strange is happening at Riverside.

As she learns about the peculiar history that connects the Green Ward patients, she discovers there is much more behind her mysterious condition than she ever imagined. Didion finds herself asking who she can trust... starting with herself.