Sinopsis dan Bocoran Ending The Grinn (2017)

A man awakens in an empty house that he is unable to leave. Battling fatigue, injury and amnesia, and guided only by a cryptic voice on his phone, he begins piecing together fractured memories of the events that led him to be trapped. With a terrifying presence confining him inside the house, he ultimately discovers a truth more horrifying than he could have ever imagined.