Delirium is a 2018 American psychological horror film directed by Dennis Iliadis and written by Adam Alleca.

[4] After spending twenty years in a mental institution, Tom Walker is released back to the mansion that he has inherited from his wealthy father, a senator who recently committed suicide.

Tom is placed under house arrest, and must check in via video phone daily for thirty days or he will be returned to the institution.

Tom suffers from hallucinations of his late father, hears noises throughout the house, and receives calls from a stranger with a garbled voice, which make him believe that he is relapsing.

He has a vision of a girl being drowned, and discovers a tongue preserved in a mason jar in the indoor pool's control panel, which he writes off as another hallucination.

Alex went on to kill another girl, which landed him in prison and Tom in a mental institution, and their mother abandoned the family in shame and disappeared.

Tom, believing himself to be stable, returns to the pool's control panel, but still finds the jar holding the tongue.

He realizes the prisoner is his mother, who did not abandon them, but was kept chained up by his sadistic father; the garbled calls were from her, as it was her tongue that had been cut out.