College student Lucy and her friends spend their vacation at her family's home in Hawaii, which includes her pet chimpanzee, Ben. However, when Ben contracts rabies after being bitten by a rabid animal, the group must fight for their lives in order to avoid the now-violent chimp.

A girl is possessed by a dark and mysterious entity. She will fight with all the elements at her disposal to get rid of it. Neither her mother, nor traditional medicine, nor a supposed expert in exorcisms, will be able to make the demon disappear, until a nun gets involved in the case and sows a doubt more terrible than the possession itself.