As House and his team are working on the diagnosis of a man with a giant, swollen tongue, the husband of a former patient walks into House's office and shoots him. House continues to treat his patient from his ICU hospital bed with the shooter, who has been shot by hospital security and hand-cuffed to his bed, as his roommate. When the after-effects of the shooting begin to impact House, he starts to question his own ability to diagnose properly. As his patient's body deteriorates, House struggles through his self-doubt and must trust his team to find a way to solve the case.