The inspiration for tonight's episode title comes from a Sesame Street book with a memorable ending. The main character of the book Grover is obsessed with figuring out who the monster is on the last page until he realizes that he is the monster. Sam's been turning more and more to his demon powers this season, so it's easy to assume the title is a shout out to his current situation.

On a couch, a guy in a bathrobe has visions of Sam and Dean. Meanwhile, Sam and Dean go to a comic bookstore for their standard questioning about a haunting. The guy working in the store thinks they're pretending to be the Sam and Dean characters from the cult book series Supernatural. Sam and Dean buy all of the books and start reading. Dean is more upset about the fact that he's naked in the book until Sam finds a few fan websites. Sam tells him about the Slash fiction and they're both equally horrified that there are fans who don't care they're related when it comes to sex.

Sam and Dean go to talk to the publisher. She's a diehard fan and explains that all anyone wants to read about are "Dr. Sexy MD," taking a slam at Grey's Anatomy. The publisher gets emotional while talking about the best parts being when Sam and Dean cry. Sam shows her his tattoo and Dean reluctantly does as well. She has her own tattoo a little lower and Dean realizes she really is a fan. She gives the boys Chuck Shurley's address.

Sam and Dean show up at Chuck's house and he immediately assumes it is a "Misery" thing, that the two are there to kill/torture him. They convince him they're the real brothers when they refer to the books that never got published and then provide their last name, which he never gave in the books. Chuck first thinks he's a God but the boys quickly provide the theory that he's a psychic fixated on their lives.

Sam and Dean go to the Laundromat, and Sam is skeptical even as Dean reads along with the scene as it happens. Chuck sees Sam talking to a blonde woman in a motel room as she motions him to a bed. Her eyes are white so it's a safe bet it's Lilith. Chuck tells the boys that Lilith comes to Sam and the two sleep together. Sam and Dean take off but Sam is still a non-believer. Dean thinks the details are wrong but the end result is the same. Dean sees the draft Chuck gives him is a way to keep everything from happening. Sam sees it as an opportunity to be ready for Lilith's arrival. Dean orders a tofu burger but still ends up with the bacon cheeseburger that Chuck wrote about.

Dean takes Sam back to the room and tells him to stay put and watch some porn. He even takes Sam's computer to keep him from researching. Chuck comes to see Sam at the motel. Chuck tells him he left the demon blood out of the books because he was afraid it would make Sam look unsympathetic. Sam still believes that he's doing the right thing even when Chuck tries to suggest that he's using the demon blood for himself. Chuck admits that he feels the story is heading to it all resting on Sam's shoulders. He also doesn't know if Sam is strong enough to face Lilith tonight.

Just like Chuck wrote, Dean sees someone trying to break into the impala and then gets hit by a minivan. Dean wakes up covered in pink band-aids and the back window of the impala is smashed out. Dean put a tarp on the window and goes to Chuck's house. Dean starts demanding answers and Castiel shows up. Castiel tells Dean and Chuck that Chuck is a prophet of the Lord and has to be protected. Castiel explains the books will be the Winchester Gospel.

Dean tries to get Sam to leave but Sam refuses. Dean finally tells Sam that he thinks he'll go dark side. Dean leaves him in the motel room. Outside, Dean prays to God for help and Castiel show up. Castiel can't help Dean but he has a suggestion. Chuck's under protection by an archangel that would kill any demon in his proximity, so Dean sets off to get Chuck.

Lilith comes to see Sam in the motel room. Sam tries to exorcise her but only blows her hair. Lilith tells Sam she'll stop her efforts if he'll agree to her terms. She wants Sam and Dean dead in exchange for the rest of the seals not being broken. Lilith found out that she doesn't live to see the end of the apocalypse and now she wants out. Sam agrees to her deal and she explains he has to sleep with her to make the deal final. Sam is about to sleep with Lilith when Chuck and Dean show up. Dean tells her about Chuck's archangel bodyguard and Lilith leaves.

Dean and Sam leave town. Sam tells Dean about Lilith's offer and Dean thinks it might not have been such a bad idea. Sam promises that he'll make sure Lilith doesn't survive the apocalypse. Back at his home, Chuck wakes up after having more flashes of Sam and Dean's future. The angel Zechariah shows up and Chuck wants to try and warn Sam and Dean. Zechariah tells Chuck that if he tries to warn them he'll stop Chuck. Zechariah tells Chuck to write.

Supernatual Cast: Jared Padalecki, Jensen Ackles, Jeffrey Dean Morgan, Nicki Lynn Aycox, Jim Beaver, Katie Cassidy, more

Story by Lauren Attaway

Starpulse contributing writer