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On The Head Of A Pin is the 16th episode of Season 4. It aired on March 19th, 2009.


Dean Purgatory Blade.png.png There was something about being there... It felt pure.

This episode summary is an official CW press release. It may contain errors.

Someone found Lucifer's sword and is using it to kill angels. Castiel (guest star Misha Collins) and Uriel (guest star Robert Wisdom) have captured Alastair (guest star Christopher Heyerdahl) and ask Dean to use the torturing skills he learned in Hell to extract information from him so they can stop the murders. Sam is concerned Dean can't handle the job but Dean agrees to do it. However, when Alastair reveals some shocking information, Dean's world is shattered.



Castiel arrives at a parking lot where the cars have been overturned and car alarms are blaring. He silences them with a gesture and goes to the center of the chaos, where a woman in white is resting, a sword wound in her sternum. He sadly wishes his sister goodbye and then disappears as the police arrive.

Dean and Sam are driving through the night from Pamela's funeral, as Sam tells Dean that Ruby is going to meet them after tracking some leads. Dean says he doesn't care and is feeling guilty and becoming tired of losing all of their friends. Sam tells him to get angry, not tired. They check into a motel and find Uriel and Castiel waiting for them. Dean snaps at them by mentioning their friend and reminds Castiel of her. Uriel is less than sympathetic while Castiel expresses his sympathy but Uriel puts him in his place, something Dean notes of. Uriel then informs the brothers that seven angels have been killed and they don't know how the demons are doing it. They want Dean to interrogate Alastair, their captive. Dean refuses but Uriel tells him they're not asking. The angels disappear with Dean, leaving Sam behind.

Dean faces his assignment with dread.

Castiel shows Dean Alastair, bound within a devil's trap in an empty warehouse. Dean tries to leave but Uriel blocks him. Castiel says they have no choice but to ask and Dean asks to speak to Castiel alone. Uriel leaves after being amused with Dean's defiance as Castiel warns that his superiors are beginning to doubt him because of his sympathies toward humans. Dean warns that Castiel won't like what walks out if Dean goes in to torture Alastair. Castiel assures him he'd give everything for Dean not to do it.

Alastair taunts Dean as he prepares to extract some answers from him.

Dean goes into the chamber alone. Alastair starts singing as Dean starts preparing a collection of torture instruments. Alastair laughs and wonders if Dean is scared. Dean denies and Alastair points out Dean left part of himself back in the pit. He suggests Dean might want to get revenge if not for how Alastair tortured Dean, then for everything he did to Dean's father John Winchester, as Dean becomes angry.

Ruby arrives at the motel and doesn't see the problem, but Sam warns that Dean can't get the job done. He's not strong enough any more, but Sam says he'll be strong enough to do it.

Dean questions Alastair's remark, as the latter boasts of what he did to John in his time in Hell but admits he never did break him the same way he broke Dean. Alastair continues by stating he expected Dean to have a similar will but mocks him on not being strong willed like his father. Annoyed, Dean tells him that he could still dream in Hell, and he dreamed of torturing him. He started with a syringe filled with holy water. Outside, Castiel listens to Alastair's screams of pain.

Sam takes a hit.

At the motel, Ruby conducts a tracking spell to locate Dean. Sam says he "needs it" and it's been weeks. Ruby tells him it'll be okay, then cuts herself on the arm. He eagerly sucks the blood from her.

Dean coats the demon-killing knife with holy water and Alastair asks if the torture will give him closure. Dean plunges the knife into Alastair, but the demon still boasts of how he changed Dean and there's no going back. Dean admits he's right, but now it's his turn. He's unaware that a water valve is moving by itself and water is dripping on the devil's trap.

Dean twists the knife.

Outside, Castiel sees the lights flickers and realizes that Anna has arrived. She's created a duplicate of her human body. Castiel warns that he still has orders to kill her, but she's sure he won't. She asks why they're letting Dean do this and questions if torturing is God's work. Castiel refuses to question the will of God, but Anna questions whether the orders are coming from God. Anna points out that he's feeling doubt and insists the orders are wrong. She suggests they can act together, but he insists that he's nothing like her. He tells her to go and she disappears.

Alastair still refuses to give the angel-killer's name. He explains that Lilith had a particular reason to get Dean, but Dean shuts him up by pouring salt in his mouth.

Alastair escapes the devil's trap and turns the tables on Dean.

As Sam drives through the night, Alastair explains that John was supposed to bring it on but it turned out that it was Dean. He describes how the first person Dean tortured was the first seal. When he broke, it broke. Alastair points out that when they summon the Apocalypse, it'll be Dean's fault. Alastair focuses on the water pipe as it continues to drip on the seal. Dean figures that Alastair is telling the truth but warns he won't be there to see it. When he turns, Alastair is free and attacks Dean. The demon hits him repeatedly until Castiel arrives, plunging the demon-killing knife into his shoulder. Castiel twists the knife but Alastair manages to pull it out and lunges at the angel. The two fight while Dean lies on the floor unconscious.

Alastair tries to send Castiel away.

Alastair slams Castiel back onto a hook, then admits all he can do is send Castiel back to Heaven. The demon starts to recite an incantation as Castiel glows with white light. Suddenly Alastair chokes and falls back as Sam arrives, using his powers to pin Alastair to the wall. Sam demands the name of the angel-killer and tortures him. Alastair says he doesn't know and finally admits the demons are not killing the angels and Lilith wouldn't stop at just seven angels. Alastair dares Sam to send him back but Sam tells him he can kill demons now. He focuses his powers and destroys the demon once and for all. Castiel just stares at Sam, in shock.

Sam gets answers out of Alastair, and then destroys him.

Sam gets Dean to the hospital and sits at his bed side. Castiel meets him outside and Sam tells him to heal Dean. Castiel apologizes, saying the trap shouldn't have broken. Sam insists that Alastair wasn't lying and they need to find out who or what is killing the angels.

Uriel is in an empty park when Castiel arrives. Uriel says he's received revelation that they've to stop hunting the demons. Even Uriel realizes something is wrong in Heaven and they wonder who could be responsible. Castiel wonders if God is punishing them, or if God isn't giving the orders any more. Uriel disappears, saying he won't wait to be gutted.

Castiel seeks some guidance from Anna.

That night, Castiel calls out to Anna and she comes. He admits he's considering disobedience but she warns that it gets worse as he exerts his independence. He flinches when she touches him, but Castiel begs her to tell him what to do. Anna refuses, telling him it's time to think for himself. He looks at a nearby drinking fountain and sees a water valve.

Castiel returns to the warehouse and examines the water valve that broke the devil's trap. Uriel arrives and ask if Castiel will fight with him. Castiel insists that no demon could have broken his trap. He talks of their time together and asks Uriel for truth. Uriel tells him that only an angel can kill an angel, and extends a sword from his sleeve. He explains that the plan was that Alastair was to have killed Dean and escaped. Uriel's plan is conversion, and he's angry that God created humans.

Anna ruins Uriel's conversion plans.

He wants Castiel to join them so that they can raise their brother Lucifer, who never bowed to humanity. Uriel asks Castiel to spread the word and bring on the Apocalypse. Uriel tells him not to be afraid and Castiel says he isn't... then slams Uriel through a wall. The two fight but Uriel quickly gets the upper hand, insisting there is no God. Anna comes up from behind and kills him.

Dean doesn't believe he is the man for the job.

Dean wakes up at the hospital to find Castiel at his side. Castiel tells him to be careful, then informs him that Uriel was a traitor. Dean asks if Alastair spoke the truth and Castiel confirms that Dean broke the first seal. They laid siege to Hell to stop him but were too late. Castiel explains that the righteous man who begins it is the only one who can finish it. Dean has no idea what it means and Castiel admits that he doesn't know either. Dean says that he can't do it, he's not strong enough. He tells Castiel to find someone else.


Main Cast[]

Recurring Cast[]


Featured Supernatural Beings[]



  • This episode is a example of how every single supernatural being has its own unique set of strengths and weaknesses for example; Alastair could push Castiel away extremely easily and was physically far superior than that he could hold him very easily by the neck, but could be injured and even almost killed by the demon-killing knife (Castiel just missed his heart and essentially only hits his shoulder), but Castiel was truly immune to the knife's demon-killing abilities when Dean stabbed him in the heart.
  • Antagonists: Uriel and Alastair.
  • The symbols used to contain Alastair were Old Enochian which, according to Castiel, cannot be broken by any demon.
  • The Angel Blades makes their first appearance on the show here.
  • The dead angel at the beginning is the only angel known in the series to have worn a full dress; all other female angels wear professional business attire.
  • Castiel was supposed to have been killed off in this episode, but due to his popularity, he remained alive.
  • Alastair makes a reference to the famous board game 'Monopoly' when he says, "Go directly to hell. Do not pass Go, do not collect $200" referring to the card that says 'Go to Jail'.
  • The name of the episode refers to a question "How many angels can dance on the head of the pin?", which was used to dismiss angelology - the existence of angels in more than one realm, and their hierarchy, along with scholasticism in general.
  • This is the first and currently only episode to feature the Enochian Devil Trap and Angelic Exorcism.


Featured Music[]

  • Cheek to Cheek - Frank Sinatra


  • Alastair: [choking, coughing on mixture of Holy Water, salt and his own blood] "Something caught in my throat... [considers] ...I think it's my throat."

  • Alastair: "'And it is written, that the first Seal shall be broken when a Righteous Man sheds blood in Hell. As he breaks, so shall it break.'"

  • Alastair: [after Castiel barely misses his heart with the demon-killing knife] "Oh, almost. Looks like God is on my side today."

  • Castiel: "You can't win, Uriel. I still serve God."
  • Uriel: [contemptuously] "You haven't even met the man! [as he brutally punches Castiel] There is no Will! No Wrath! No God!" [he is suddenly stabbed through the throat from behind]
  • Anna: [leaning in close from behind; whispering in his ear] "Maybe. Or maybe not...but there is still me."

  • Alastair: "Go directly to hell. Do not pass go, do not collect $200."


International Titles[]

  • Brazil: Na Cabeça do Alfinete (On the Tip of the Pin)
  • German: Teuflischer Engel (Diabolic Angel)
  • Italian: Sulla punta di uno spillo (On the tip of a pin)
  • Hungarian: Vallatás (Interrogation)

External Links[]

IGN review- View Here