Sam, Dean, and Castiel (who has decided to become a full-time hunter) investigate a string of deaths in Oklahoma City, Oklahoma that appear to have been inspired by cartoons – a man's heart literally bursts out of his chest when near a woman he likes, a man hovers in midair for a moment while jumping off a building, and an anvil crushes a security guard. Meanwhile, Dean and Castiel have a heart-to-heart about Castiel's mental state and the ramifications of his actions as "God." The Winchesters and Cas determine that the cartoonish effects are caused by an old man, named Fred Jones (Mike Farrell), who has reality warping powers, and is currently living in a dream world inside his mind while residing in an assisted care facility. Fred is being used by a doctor at the assisted care facility to rob other elderly patients of their valuables. While Dean confronts the doctor, Sam and Castiel enter Fred's mind to speak to him. Sam is able to convince Fred to give up living in a dream world and come back to reality, causing the reality warping effects to end. Fred forces the doctor to kill himself and has Castiel remove his powers so he is no longer a threat even though it leaves him in a mentally damaged state. Castiel decides to return to Heaven to face up to his actions, but is forbidden from doing so by Naomi. Instead, Castiel decides to watch over Fred for a while. In flashbacks, Sam meets Amelia's father who is initially cold towards him, but eventually warms up to him just in time for Amelia to learn that her husband is still alive.
Source: Wikipedia
Source: Wikipedia