The Evil Within is a 2017 American horror film written and directed by Andrew Getty and starring Sean Patrick Flanery, Dina Meyer, Frederick Koehler, and Michael Berryman.

As an adult, Dennis has one where a living demon, called the Cadaver, fastens a zipper onto his back and enters his body.

Dennis continues to have nightmares of the Cadaver and his reflection informs him that in order to get rid of it, they need to start killing animals.

He begins working in the secret cellar, which perplexes John, especially when he sees that Dennis has videos on taxidermy.

When John and Lydia take Dennis to his favorite restaurant, he supposedly kills a man in the bathroom without hesitation, scaring himself.

John reveals to Lydia his secret: Dennis was a child prodigy whose works had been published in the newspapers.

Dennis appears with a now-stuffed Lydia and puts on a ventriloquist act and John realizes he is glued to the chair.

The previous victims have all been stuffed and are used in an extravagant diorama revealing that John intentionally knocked Dennis down the stairs to get rid of him.

According to a post-production producer who had worked on the film and a friend of Getty, Ryan Readenour: "When he was young he would have these really powerful, sick, twisted dreams, and [they were] so shocking to him that he didn't think they came from him."

He made his own unique camera rigs, built expensive sets, and with his FX team he created elaborate animatronic robots, including an octopus that can play a drum kit.

[3] The production however would stop and start over many years as it was beset with funding issues and conflicts with the cast, including a lawsuit from a studio assistant.

[4] This was the final film to feature Matthew McGrory who appeared in an uncredited cameo from footage shot before his death in 2005.

[5] The health conditions of both McGrory and Berryman (who had been ill for some years) had slowed down the production and scripted scenes had to be replaced.

[15] Charles Bramesco of The Guardian considered the film "very clearly the handiwork of a rank amateur under the influence of powerful narcotics", but that "Getty’s monomaniacal drive and technical knowhow resulted in some truly outré horror", and that his "wild experiments with the form command respect".