Duncan's life takes a bizarre turn when he discovers that the severe stomach problems he's been experiencing are actually caused by a demon living inside his intestines. As the demon comes out to exact revenge on those who have wronged Duncan, he must find a way to control it before it destroys his life and relationships.

Anna, editor-in-chief of a news magazine, and her husband Daniel, founder of an AI-centered home security company, are threatened by a mysterious house guest as they expect their first child.