Back at the CIA, where everything is super-intense thanks to the frequent a steadicam shots of Dr. Terzzzi walking purposely down the hall with House and Curtis at her heels, Terzzzi says they've run a bunch of tox screens and tested for all kinds of other environmental stuff. Everything's been negative. Curtis notes that John ate a lot of chestnuts recently. House scoffs at this fact being at all important, but Curtis points out that poisonous horse chestnuts look like regular chestnuts. House says that they taste a lot different, so he doubts that John would accidentally eat enough of them to get sick. Dr. Terzzzi makes sure to stare at House lovingly. Very subtle.

House demands to know where John was last, saying if they don't know what kind of environmental factors they're dealing with, there's no point in having him or Curtis there. Dr. Terzzzi's steadfast resolve not to tell them classified information crumbles instantly and she reveals that John was in Bolivia for the last eleven months. House tries to wrap his mind around who's in Bolivia for the CIA to assassinate aside from his former housekeeper, who has it coming because "cleaning the windows means cleaning both sides. Am I right or am I right?!" House demands that last part of Curtis, who looks disgusted. I guess he doesn't like dirty windows either. Anyway, House has the entire case figured out: John has pancreatitis brought on by excessive alcohol consumption. This does not explain John's gross fingernails or skin burns, however. House says they're simple fungal infections and sunburns, although I have seen sunburns before and they never looked like John. I have also seen pancreatitis, and it's fairly easy to diagnose with lab tests. If it's severe enough, you can diagnose it just by looking at the patient's blood serum, which is all milky and pink from the fats he can't dissolve. I guess the CIA medical lab doesn't have those simple tests, though. Or eyes. Curtis, by the way, thinks they're looking at an assassination attempt from a group with the resources to create an untraceable radioactive isotope. You know, if you have the resources to make something like that, why not use them to cure cancer or something instead, spies? Come on now. Terzzzi goes with Curtis' diagnosis because it's a lot cooler.