Chase gets home. Park's grandmother is on his couch, knitting. Park is there, too. She explains that the grandmother will be gone in an hour. She's here because her father is getting a cyst removed. Chase comments, "She seems awfully quiet." Park answers, "You haven't seen her drunk.
Taub checks on Hatcher, who's not in his bed. He's sitting on the floor, crying.
The team gathers in the external office. Park doesn't think the crying was a symptom. Taub says it's chronic traumatic encephalopathy, caused by repeated blows to the head. House calls Hatcher a talentless bum. Park announces that she moved into Chase's apartment. "We're not having sex. With each other." House: "Yet." Park: "Yes." Chase: "Yet?" Anyway, the only test for CTE is postmortem. He's only had three concussions, which isn't enough to cause CTE. Well, he might have had more. House decides that Chase isn't trying to sleep with Park; he just feels guilty.
In a diner, a disturbingly polite young man named Duncan is there to meet Wilson. Wilson gives him a present. It's something called a Gamedeck, which Duncan already has. The waitress is impressed with it, though.
Taub tells Hatcher that his psych evaluation says he's happy. Hatcher knows about CTE and doesn't want an MRI. He already has plenty of evidence of head trauma.
Oh, we're back to Wilson. I was hoping we were done with this. They have awkward conversation and Duncan has to leave. Would Wilson like to hang out again? Tonight? He stammers a bit, but the answer is yes. Duncan will text Wilson.
Taub joins Chase in the MRI Scanning Booth. Apparently Chase convinced Hatcher to get the MRI after all, but he says the scan is clean. Taub disagrees and points to what he says is evidence of trauma. But it wasn't Hatcher after all! It was House in the MRI tube, laying a trap for Taub. But then: BEEP BEEP BEEP BEEP! Chase announces that the patient's stroking out. Taub and Chase go to the patient, leaving House in the tube. Oh, the hijinks!
House himself studies Hatcher and announces that he didn't have a stroke, but he also doesn't have CTE. But he's definitely got something. Taub absorbs some abuse from House. Everyone but House leaves so Hatcher can tell him something. When House comes out, Taub suggests neurosyphilis. House tells Taub that Hatcher told him to apologize to Taub or he (Hatcher) would excrete down his (House's) neck. Chase pitches a bunch of medical stuff and House authorizes the treatment.