text: Patient Z had been diagnosed with schizophrenia accompanied by paranoid delusions. What made him unusual was that his delusions seemed to be contagious. Several other mental health professionals had come to share some aspects of the patient's psychosis after interacting with him. To avoid preconceptions I had only studied observations of his behavior, rather than diagnostic sessions. When the orderlies brought him into my office, they allowed him to enter by sliding with his back along the walls. We had placed his chair against the wall and positioned my desk facing his chair. Once seated, he seemed calm and rational, though his eyes indicated a lack of sleep. "Good morning, Mr. Z. How are you today?" "As usual, doctor. And you?" "I'm fine." I looked down at my notes. "Do you know why I'm here?" "You want to ask me questions. To find out what's wrong with me." He looked at me. He was able to make eye contact but not sustain it, his gaze frequently flicking up and over my head or shoulder. I made a note. "You either won't believe my answers, or wish you didn't." "I'm prepared to listen to you with an open mind, Mr. Z." He stared at me for a long moment. "I'll tell you what you want to know. Why not? Don't say I didn't warn you." "Would you like to tell me what's going on in your own words?" He looked over my shoulder organising his thoughts. The he looked down and met my gaze. "Have you ever heard of P.T.?" "Do you mean 'physical therapy?'" "In this case, 'P.T.' stands for 'playable teaser.' It was a demo released by Konami for an upcoming video game in 2014. It was wildly popular but was withdrawn from circulation some six months later." I made a note. "If it was so popular, why did Konami withdraw it?" "The official reason was that the game's creator, Hideo Kojima, had a falling out with Konami." "That's not the real reason?" Z paused for a long minute. "Point of no return, doctor. Do you really want to know?" "Of course, Mr. Z." "OK. It's on your head." I waited for him to continue. "What you have to understand, doctor, is that playing this demo is profoundly disturbing. As you play you are stalked by a ghost or creature named 'Lisa.' Data miners discovered that Lisa is always behind you, though you can't see her. Eventually you get hints that she's following you around. Shadows and noises, sound effects ..." He trailed off, staring upward with haunted eyes. "Mr. Z?" He seemed to recover his composure. "Sorry doctor. Anyway, the lucky players, the smart players ... stopped playing. The others ..." Again, I waited. "The unlucky players found that their perceptions had been ... heightened. They began to see things. In reality. Things children sometimes see but stop seeing as they age. Do remember seeing the boogeyman as a child, doctor?" A shadow seemed to fall over him. It's not beneficial to engage patients in their delusions, but he had struck a chord. "Yes. It had empty eye sockets and ..." "Purple hair. It is a creature of unspeakable horror." He swallowed, and again he looked over my head. "It's standing right behind you, doctor." I felt a chill down my back, and the hair stood up on my neck. I carefully rolled my chair to the wall behind me, all the while dreading that I would bump into the thing behind me. Never to be safe again.