Outside. Holmes says that whoever cut up the pancake killed him. He doesn't like proposing a theory before its complete, but the killer was medically knowledgeable and Mr. Kelty had a friend claiming to be a doctor. And the killer cut up the pancake into child-size pieces, suggesting that he viewed his victim as someone to be taken care of. The point is, it's an Angel of Death. That's "someone who kills sick people in the hospital."
Mr. Baldwin, the head of surgery putts in his office (because all fancy doctors on television have teeny putting greens in their offices) and isn't convinced of the Angel of Death hypothesis. Holmes demands access to all medical records and epinephrine records anyway. Dr. Baldwin says Mr. Sanchez is in charge of that stuff, but Holmes says that Baldwin's smile from earlier (when he made a short joke) means he doesn't like Sanchez. Indeed, Baldwin will help.
Holmes looks through medical records. Watson wishes him luck and Holmes says this, which is awesome: "Luck is an offensive, abhorrent concept. The idea that there is a force in the universe tilting events in your favor or against it is ridiculous. Idiots rely on luck." Right on, man. Anyway, Watson points out that she could be useful here, what with her having actual medical knowledge and all. Holmes has a chalkboard with all 73 possible victims, although obviously some are going to be legitimate deaths. Watson suggests checking the epinephrine records. There have been two thefts reported from the pharmacy, but they don't match up with any deaths. Watson proposes crash cart thefts, since crash carts are left unattended all the time. There are several precise dates that match deaths. There were no reports because hospitals normally only care about things like oxycodone. So they have nine deaths to investigate.
Holmes now has twenty-three suspects based on people who worked on the relevant dates. He worked on nurses as well as doctors on the theory that their last victim was blind. So even though he told perfume lady he'd been talking to a doctor, he doesn't really know. Watson leaves to go talk to Carrie. Holmes enters the elevator with that janitor he shoved out into the hallway. The janitor claims to accept Holmes's apology but he still pushes all the elevator buttons as he rolls his cart out into the hallway..