At the Walsh's, a seedy looking doctor apologizes to Liddy because "it's" metastasized. The word cancer got bandied about a lot less then. Her father's cancer is in his lungs, liver, everywhere. Liddy pleads with "Dr. Brown" to do something, but she should have called him Dr. Yellow, because when he says there is a cure, and explains that all she'll have to do to get it is "something" 10 years hence, that's the color his eyes turn. Grandpa Samuel busts in with a shotgun and blows a hole in Dr. YED that throws him back down on the couch. My phone rings, but I ignore it. YED then magics away Grandpa's shotgun, telepathizes him up against the wall, and Liddy screams all the while. Mary surprises YED from behind. She's got a knife (too bad it's not Ruby's), and slashes at him. Girl's got form and YED likes her spunk. He thrusts her against a wall, busting a mirror with her head. Dean bursts in and booms, "Hey. Let her go!" YED uses Mary as a human shield and asks Dean where he got that gun. Dean's ready to take a shot so YED exorcises himself from Dr. Brown's corpse like the black, projectile vomit he is.
Outside, Dean questions Mary on what else the YED said to her, but she says he just said he liked her, and she wonders what he meant by that. Samuel comes out, pronouncing Liddy a strong kid who'll be fine, and my spider senses tingle. Mary's creeped out and wants to leave, so she gets in the car. Samuel congratulates Dean on a job well done in there, but Dean is utterly destroyed by the fact that he didn't kill YED. When Samuel tells Dean to take the compliment - that he's saying he was wrong about him, Dean looks at his painfully young mother waiting in the car, and tells Grandpa he needs to talk to him...alone.
In the Campbell's dining room, Dean tells his grandfather everything -- starting with the most important bit -- that they have to kill this thing before Mary dies. Grandpa's disturbed and skeptical. "What are you -- some kind of psychic now, too?" Dean sits next to him. "Listen to me. Now this is going to sound a little crazy. Actually, it's going to sound massively, massively crazy." At least he's self-aware. He explains that Mary's his mother, John's his father, Samuel's his grandfather; that he was born January 24, 1979. Samuel says he doesn't have to listen to this but Dean persists. "Mary was killed by a yellow-eyed demon in 1983 and I think that this, what happened tonight, that this is the moment that he caught her scent." What is with the monsters and the smelling? It's so gross. Dean explains that if they don't kill this thing and it gets away, that Mary will die. "So I'm asking you, please..."