This week, a prosecutor comes into Princeton Plainsboro with chest pains. As his symptoms worsen, Park and Adams discover a secret arsenal in his home and begin to question his sanity. The arsenal has all the doctors arguing over whether the patient is truly paranoid or if he's normal to feel unsafe, and as a result, keep all those guns in his house. As Chase, Park, Taub, and Adams discuss whether paranoia is a symptom, Park starts to get the feeling no one likes her.
As Park tries to pinpoint the reasons why Adams and Chase picked Taub over her, Adams begins to overcompensate for the way Park is feeling, making Park even more insecure. Meanwhile, Chase and Adams exchange niceties and flirt.
Foreman is also feeling flirtatious, despite his best efforts to deny he wants or needs a woman. Taub and Chase think Foreman needs to get out more, and Foreman meets a woman at the gym. Things start to heat up, but it turns out she's married. At the end of the episode, Foreman decides to go for it anyway.
As for House, he is preoccupied trying to prove Wilson wrong. Wilson believes House owns a gun and the two try and best each other throughout the episode. It turns out, House owns a fake gun, but that's all. Wilson admits he's wrong and bows out of House's office. In the last scene, House looks at the gun, and then pulls down his father's sword.
In the last few scenes, the patient is diagnosed with diphtheria and finally, in the elevator with Chase, Park, and Adams, Park asks Chase out for a drink and as much as he tries to get out of it, he ends up saying yes to her while Adams looks on, desperately uncomfortable.