House is in his office talking to himself when Leon passes by and thinks House is talking to him. He asks House if he is, and House, who is stuck for ideas, calls Leon in to help with his differential diagnosis of Megan Bradberry.
He asks Leon to pretend he has a favorite floor buffer that isn't working. After Leon accepts the premise, he suggests that maybe something fell on it or fell into it. House uses those to come up with ideas like trauma or toxins, but rejects the ideas. Finally, Leon suggests it might be lupus because his grandmother has it.
House feels he has to do an environmental scan and asks Leon to come along to help. However, Leon refuses on principle, although he soon asks for $50. House thinks that's too much and cons Wilson to help.
After House comes up with an idea, he has to convince Mrs. Bradberry to consent to treatment. As House tells Mrs. Bradberry the risks and consults with Leon, who now goes by the name "Dr. Buffer", Leon keeps asking Mrs. Bradberry to sign the consent form over and over again. Mrs. Bradberry and Megan's boyfriend Ben finally realizes something is up.
House then has to deal with Cuddy who lets Leon off the hook completely and instead reprimands House for trying to pull a fast one on the family.