Sam, when Dad told me that I might have to kill you, it was only if I couldn't save you. Now, if it's the last thing I do, I'm going to save you.
Written by Cathryn Humphris.Directed by J. Miller Tobin.Airdate: February 8, 2007.Sam calls Dean from Twin Lakes, Wisconsin, after having disappeared for a week. Sam claims to have no memory of what he did in that week.Sam disappears for over a week, and then calls Dean from Twin Lakes, Wisconsin. Dean finds Sam in a motel room with bruised knuckles, covered in someone else's blood, and unable to remember anything that happened. Sam seems overwhelmed by the possibility that he may have surrendered to the fate the Yellow-Eyed Demon has planned for him, but Dean will not accept this and insists they work this like any other case. The investigation leads them to the home of Steve Wandell, a hunter they do not know. The brothers find Wandell's body and security tapes showing Sam murdering Wandell. Sam then insists that Dean kill him so that Sam will not hurt anyone else. When Dean says he would rather die then kill Sam, Sam says, "No. You'll live. You'll live to regret this." Sam then pistol-whips Dean, knocking Dean out.After Dean wakes up, he is able to track the GPS on Sam's phone to Duluth, Minnesota. He arrives to find Sam holding a knife to Jo Harvelle's throat. Sam asks Dean to kill him before he kills Jo. Dean lowers his gun and turns away, only to surprise Sam by dousing him in holy water and revealing that Sam is possessed by a demon. Dean chases demon-possessed Sam out on to a dock, where the demon shoots Dean, and Dean falls into Lake Superior. Demon-possessed Sam leaves, believing Dean dead, but Jo hears Dean's ringtone, drags Dean out of the lake, and patches up the gunshot wound.Dean realizes that Sam probably went after the nearest hunter, Bobby Singer in Sioux Falls, South Dakota. Bobby realizes that Sam is possessed when he chokes on a beer laced with holy water. Bobby knocks the possessed Sam out and binds him to a chair under a devil's trap. Dean arrives in time to help Bobby try to exorcise the demon, but they are unsuccessful due to a binding brand on Sam's arm. The demon uses an incantation to crack the ceiling and break the devil's trap. The demon then reveals that she is the same demon that possessed Meg and that she crawled her way out of Hell to be able to torture the Winchesters. While she is beating up Dean, Bobby manages to burn the binding brand on Sam's arm with a hot poker, and the demon leaves Sam's body.Bobby warns them that Steve Wandell's hunter friends are after his killer and gives them anti-possession charms. Dean and Sam set off on the road together.
For this episode = One human, a hunter murdered by Evil!Sam.For the series so far = At least 176 humans; 12 ghosts; 5 vampires; 2 shapeshifters; 1 demon; 1 god; 1 rakshasa; 1 rawhead; 1 shtriga; 1 wendigo; 1 zombie.
Artistic License - Geography: Sam says the receipt is from a gas station a few towns over. However, we later learn the gas station is located on Route 71, which is in Minnesota. It would likely take over 6 hours to drive from Twin Lakes, Wisconsin to Route 71.
Bobby Singer mentions it has been a while since he has seen Sam, and proposes a toast to John Winchester. The last episode with Bobby in it was "In My Time Of Dying" (S02, E01), but the brothers stayed at his salvage yard while they repaired the Impala and tried to come to terms with their father's death in "Everybody Loves A Clown" (S02, E02).
When Evil!Sam sees that Dean did not drown in Lake Superior, he says, "Dean, back from the dead. Getting to be a regular thing for you, isn't it? Like a cockroach." While Dean has not actually died yet in the series, he was meant to die and had a Reaper after him in "Faith" (S01, E12) and in "In My Time Of Dying" (S02, E01).
The motel room in Twin Falls, Wisconsin is decorated with fish hanging between red and white bobbers. Dean is fishing for answers, but in actuality Sam is being used as bait by Meg who is reeling Dean into her trap.
The fishing theme is continued at the Sandpiper Tavern, where several fish specials can be seen on the menu on the wall. In the Sandpiper Tavern, Jo serves as bait.
Faking Amnesia: The Meg demon possessing Sam pretends Sam is suffering from amnesia to get Dean to investigate what Sam did and discover Wandell's murder, so Dean will believe Sam has surrendered to his dark potential.
Laser-Guided Amnesia: It initially appears that Sam can't remember what the hell happened in the past week. But since he was possessed all along, this turns out to be a lie to make Dean investigate and find out that Sam has apparently turned evil.
Out-of-Character Moment: The whole episode for Sam and Meg. The why for Sam is obvious. It's Fridge Logic for Meg, especially in later seasons—she claims in past and previous episodes to have Undying Loyalty to Azazel and Lucifer, yet here she says she doesn't care about their plans anymore and in fact nearly sabotages it by trying to get Azazel's favorite special child/Lucifer's true vessel killed.
Ship Sinking: For Dean/Jo. Sam says that Dean doesn't like her that way, thinking of her as more of a little sister, much to Jo's anger. Later on, Jo recognizes that Dean doesn't see her as an equal and that he won't call her, even though he says he will. The ship is revived, though, in "Abandon All Hope" (S05, E10).
Tracking Device: Dean gets the phone company to unlock the GPS on Sam's phone by claiming his son, Sammy, is a diabetic he is worried about after not coming home on time after a Justin Timberlake concert.
Wall of Weapons: Sam uses Dean's lockpick to open a closet at Steve Wandell's home and finds one, the first clue that Wandell was a hunter.