The Hobgoblin of Little Minds — Mark Matthews

Kori Persephone Driscoe suffered through her dad's mental illness. All she wanted was for him to get better, but instead he disappeared. Kori trespasses into the abandoned Northville Psychiatric Hospital, the last place her dad was treated, seeking solace and traces of his memory. What she finds instead is something no longer human living deep in the underground tunnels. During the last days of the hospital, a rogue psychiatrist had been manipulating the mood swings of the mentally ill, transforming patients into savage, manic creatures who seek justice by the light of the full moon. When the creatures hunt for prey, only an escaped patient and her beloved child can help Kori survive. But they better act fast, because the creatures want blood, Kori wants to save her dad, and the whole hospital is about to be blown to pieces and bury Kori alive.