Cuddy is out jogging and gets back home to talk to her handyman, Alfredo, and insists he stay to finish her roof even though he isn't feeling well. She goes inside and then Alfredo falls off the roof. Cuddy rides with him in the ambulance going to the clinic and notices his two little fingers are darker than the others.
House looks into the matter and suspects clotting problems, and has his staff run tests, taking over from Cuddy. Stacy warns her not to get involved while Alfredo is eager to get out so he doesn't lose his regular job. Alfredo is having a third finger turning dark and Cuddy offers a protein-c treatment that House considers risky. Meanwhile, Foreman is treating a clinic patient, an African American, and recommends a blood-pressure treatment. The man, Robert, is skeptical of the treatment and considers it racist. Alfredo gets right-side paralysis as a side effect of the protein-c treatment and they call in a neurosurgeon to operate.
After the surgery Alfredo develops a bad cough and his temperature is spiking while his fingers get darker and he has an infection in his lungs. Cuddy insists on riding the team on their differential diagnosis and House suggests he was sick before he fell. Cuddy reveals Alfredo had asthma. House insists they check out Alfredo's house and sends Cameron and Cuddy goes along, while House has Chase and Foreman sneak into Cuddy's house and he tags along. Stacy hits up Wilson for info on House and shows a bit of jealousy. Cameron and Cuddy find that Alfredo's roof is leaking, cockroaches, and a dead rat. Cameron brings up why Cuddy doesn't fire House, while House finds black mold at Cuddy's house.
Alfredo has rat bites while House reveals the presence of mold and the x-rays confirm the fungal infection is more likely. While they give him treatment, Manny, Alfredo's younger brother, hit Cuddy up for a job and accuses her of not caring. House and Stacy exchange words about Cuddy's guilt and House's control issues. House gets together with Robert who didn't take the medicine, and who thinks House is a racist too, so House gives him "Republican" medicine. Alfredo isn't getting any better and is suffering kidney malfunction.
They confirm it isn't either rat bite fever or fungal infection and when House checks up on Alfredo, he discovers the hand is rotting. House proposes amputation and Cuddy is reluctant to allow it since Alfredo won't be able to work – House accuses her of losing perspective. Cuddy eventually agrees and tells Alfredo about the treatment, and he reluctantly agrees. Foreman consults House over Robert's treatment and House reveals he gave him the same medicine Foreman did, but Foreman still isn't happy for House doing him a "favor." Alfredo undergoes the surgery, but the necrosis has spread to his other hand.
They go back to checking the symptoms and noting a lack of DIC and House concludes Alfredo's heart is infected and it broke off and went to first one hand and another. House concludes it's parrot-related and orders treatment. House confronts Alfredo and brings him out of unconsciousness but when Cuddy doesn't allow it, House figures he'd be out dancing. The staff head out to where Alfredo would have gone and find…cockfighting. Manny is working there as well but Alfredo's asthma made him vulnerable. Cuddy is feeling guilty and House announces Alfredo is suing them – Cuddy is okay with that, and with a little prodding from Stacy, he confronts Cuddy over her guilt and (more or less) makes her feel better. Alfredo is left to consider his missing hand, while Cuddy deals with her leaking roof and her guilt.