Malleus Maleficarum

Malleus Maleficarum is the 9th episode of Season 3. It premiered on January 31st, 2008. 

Summary
Unrequited love becomes vengeful witchcraft, which in turn leads Sam and Dean to a coven of suburban witches whose black magic is drawn from a much more sinister source.

Synopsis
After arriving home from a party, Janet Dutton starts brushing her teeth, only to have them start falling out. Soon after, her husband, Paul finds her dead on the bathroom floor. Posing as investigators from the Centers for Disease Control (CDC), Sam and Dean interview Paul and search the house. Dean suspects Paul is lying about something, and Sam finds a hex bag hidden in the bathroom, indicating a witch was involved.

That night a woman, Amanda, casts a spell and Paul Dutton nearly dies while eating a burger that becomes infested with maggots. He is saved when Sam and Dean arrive and burn a hex bag they find in his car. When the spell unexpectedly ends, Amanda panics before being attacked by a mysterious force that slashes her wrists causing her to bleed to death. Paul admits he had an affair with Amanda, which he had ended the previous week against her wishes. When Sam and Dean arrive at her home, they find her dead, surrounded by the paraphernalia of witchcraft.

Elsewhere in the town, three of Amanda's neighbors, Tammi, Elisabeth, and Renee, meet under the guise of a book club, but it soon becomes apparent that they are practicing witchcraft.

The next day, Sam and Dean interview the women and while they don't learn much, research shows that a couple of the women have lately had a run of successes and windfalls. Sam suggests that they will have to kill the women as they are using dark magic and have murdered.

As they head back to their motel, the Impala is stopped when Ruby appears on the road. She tells them that a demon is in town, controlling the witches, and that the demon will come after Sam, and advises him to leave immediately. Dean argues that they shouldn’t listen to her and draws the Colt, but Sam stops Dean just as he tries to shoot Ruby, who vanishes.

At the motel, Dean questions Sam as to why he is no longer concerned over taking human life. Sam admits he is trying to be more like Dean, to prepare himself for dealing with the demon war after Dean is dead. Suddenly Dean feels intense pain, and starts vomiting blood. They suspect it is a spell caused by the coven. Unable to find a hex bag, Sam grabs the Colt and takes off to confront the women.

At the house, they deny all knowledge of what is happening to Dean, until Tammi reveals herself to be a demon, killing Renee.

Back at the motel, Ruby arrives and doses Dean with a potion that saves him.

Sam tries to shoot Tammi with the Colt but she stops the bullet in mid-air, and then uses her power to pin Sam to the wall. She tells him that a new leader has arisen to lead the demons, and that he wants Sam eliminated. Dean arrives, but is also attacked by Tammi.

When Ruby appears, she pretends she has led the Winchesters to Tammi in order to gain her favor, but then tries to kill Tammi with her knife.

Tammi overpowers Ruby, and reveals that Ruby was once a witch who sold her soul to a demon – Tammi. Just as Tammi is about to kill Ruby, Elizabeth starts a spell. Although Tammi kills her, she is distracted long enough for Dean to grab Ruby's Knife and kill her.

Later that night, Ruby visits Dean and admits that she can’t save him from Hell. She tells him that all demons were human once, but that Hell strips away their identity. She also tells Dean that the same will happen to him and that there is no way to stop him from going to Hell. She says she wants him to help prepare Sam to fight the demons after Dean is gone. Ruby retains a memory of what it was to be human and wants to fight on the side of humanity.

Featured Supernatural Being

 * Witch
 * Demon
 * Astaroth
 * Ruby

Featured Music
"Every Rose has its Thorns" by Poison

"I Put a Spell on You" by Screamin' Jay Hawkins

Continuity

 * Though this is not the first time witchcraft is seen being used, it does mark the introduction of human witches.
 * The main antagonist of the third and fourth season, Lilith, is referenced for the first time by the demon possessing Tammi.
 * Demons are revealed to be corrupted versions of human souls through torture in Hell.
 * This is the first time Dean actually sees Ruby in person, although they have been in the same place at the same time before in "Magnificent Seven" and "Sin City."
 * When Dean sarcastically says "So the devil may care after all?" to Ruby at the end of the episode, she quietly replies, "I don't believe in the Devil," referencing the demons' belief in Satan as their god (first shown in "Sin City"). The next season's finale, "Lucifer Rising", revealed that Ruby's goal in aiding the Winchesters all along was in fact part of a ploy to free Lucifer from his imprisonment in Hell.

Trivia

 * Before it aired, this episode was initially titled "Witch Hunt". It was also supposed to feature a demon framing a group of innocent women as witches to have them murdered, but this idea was dropped because it was too similar to the plot of previous Season 3 episode "Sin City".
 * The title of this episode, "Malleus Maleficarum" (meaning: Witch Hammer) is the title of a book first published in 1486, which basically served as the Inquisitor's how-to manual of identifying and destroying witches during the Inquisition.
 * This episode is widely regarded as a spoof of the TV series Charmed (which shares some similarities to Supernatural in the sense that both feature siblings battling paranormal forces of evil); the German dub of "Malleus Maleficarum" even features the witches being voiced by same voice actresses who voiced Charmed lead protagonists Piper and Phoebe Halliwell and Paige Matthews.
 * Sam and Dean's agent names Bachman and Turner refer to the band Bachman Turner Overdrive.
 * When Amanda flips through her book in a panic after failing to kill Paul, some of the text is in Irish (Gaeilge). A lot of it seems to be taken from the Irish translation of the Christian "Lord's Prayer", although the wording has been altered quite a bit in some of the lines. Examples include “Ár n-Athair atá ar do riocht” (Our Father who art in your kingdom) and “ach soar sinn ó olc” (but deliver us from evil).

Quotes
(Ruby bursts into the room as Dean is dying.)

Dean: "You wanna kill me? Get in line, bitch!"

(Ruby gets Dean, throws him onto the bed, and starts pouring a liquid down his throat.)

Ruby: (panting) "Stop ... calling me ... bitch!"

Dean: "You saved my life."

Ruby: "Don't mention it."

Dean: "What was that stuff? God, it was ass. It tasted like ass..."

Ruby: "It's called 'witchcraft', shortbus."

Dean: "You're the shortbus ... shortbus."