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Hello, I'm looking for a movie that touched me, but obviously I can't find it. I would be very happy if you help me with this.

Description: a possible future, people have advanced in the study of human consciousness, they can carry out a procedure that introduces the consciousness of one person into another.
Everything happens around one patient, he seems to be some kind of maniac. They decided to help him. One of the conditionally psychologists decided to infiltrate his mind and help him understand himself, and there was some other goal, to learn something from him. So, she comes to him, looks, goes nuts, then she drags her in and they can’t let her out of his head, he has 2 subpersonalities in his mind, which are the main ones - the child and the "king of evil". The child helps the psychologist in every possible way, but he is a weak part of the patient's personality, subordinate, there is also the king of evil, he personifies everything bad that is in this cell. The ending of the film is based on rescuing the reasoner from the maniac's head, and the maniac seems to become a vegetable. Something like this )