The episode begins with a prologue by Lilith. Lilith explains that she had been wondering in the wilderness for months if not years when everything outside of the Garden of Eden was still a stony wasteland. Lilith encountered Satan, whom she describes as a beautiful angelic man with two wounds on his back. He lifted her up and she helped him and healed him. Lilith named the man as Lucifer, who was soon to be their Dark Lord. She describes herself as his handmaid and Lucifer as her master.
In the present, the Dark Lord emerges from Hell into Greendale's forest in human form. Meanwhile, Sabrina returns home. Zelda asks her where she has been all night and asks if she knows about the troubles they have been through. Sabrina tells Zelda and Hilda to listen as she explains that "Ms Wardwell" manipulated her into fulfilling a prophecy meant to bring about the end of the Dark Lord. She explains that the Dark Lord is in human form and is somewhere in Greendale. Sabrina says that the Gates of Hell are about to open, releasing the hordes of Hell.
Hilda is shocked. Nick explains that the Dark Lord's plan is to enslave the tribes of human and witchkind and to rule over everything with his demon army. Ambrose explains that Sabrina created a mandrake that absorbed all her witch powers. Sabrina says that is not even the worse of it. When Zelda asks what is worse than being mortal, Ambrose explains that Sabrina is meant to rule as the Dark Lord’s Queen. Zelda objects because Sabrina is too young and vows to stand against the Dark Lord for her family.
Zelda tells them to build a protection around the house. Working together, the Spellmans and Nick erect a protect around the house. Nick tells Sabrina that they need to find where in Greendale the Dark Lord is. Shortly later, Harvey arrives with Roz and Theo. Sabrina reassures her friends that she is the real Sabrina and not the doppelganger. Harvey demands to know what is going on. Sabrina explains that the Dark Lord is in Greendale and that he wants to jumpstart the Apocalypse by opening the Gates of Hell.
Harvey deduces that the Gates of Hell are in the mines and offers to help. Nick advises him to sit out but Harvey convinces Sabrina to let him and her other friends help. Nick reminds Sabrina her friends are mortal but Sabrina reminds him that she is also mortal. Sabrina tells her friends to find a way to keep the Dark Lord's forces from opening the doorway. Harvey suggests dynamite and Sabrina approves of the plan and tells them to be careful. Zelda calls Sabrina inside while Sabrina tells Nick to be careful and stick to the shadows. She kisses him before leaving.
At the Academy of Unseen Arts, Prudence approaches Dorcas and Agatha, telling them that she needs their help. They initially decline because they lack the Blackwood name. Prudence tells them of her plan to kill Father Blackwood. Agatha and Dorcas ask how they will do it since he won’t let them get close, Prudence replies that they don't need to and shows an object covered in a red cloth.
At Dorian Gray's Room, Dorian Gray is visited by a naked Lucifer. Gray doesn't recognize the Dark Lord at first but likes the naked man. The Dark Lord reminds Dorian that they struck a bargain of eternal youth for his youth. Dorian Gray is taken aback and apologizes to the Dark Lord. The Dark Lord demands where Lilith is and she surfaces.
The Dark Lord expresses surprise that she did not greet him in his angelic form. Lilith says she has been busy preparing the way. He notices that Lilith seems perturbed. Lilith is unhappy that Sabrina is inheriting the throne and crown that were promised to her. Lucifer replies that it is not her turn yet. Lilith drinks a cup and says not ever. The Dark Lord promises that she will lead the armies of Hell when the gates open. Lilith responds that is just a supporting role and asks why he chose Sabrina over her. The Dark Lord replies that he is bored with her self-pity and orders her to bring Sabrina Spellman immediately. The Dark Lord says he will attend to certain wayward members of his flock before drinking a glass of wine.
Back at the Academy, the Weird Sisters dance around a statue of Father Blackwood while holding a long red cloth, singing a song. Blackwood starts to bleed from his nose. Just then, Melvin enters Blackwood's office to inform him that the Dark Lord has returned in his angelic form and awaits his presence at Dorian Gray's Room. Blackwood thinks that the blood is a sign. He tells Prudence that the Dark Lord has summoned him and that she must also come with him.
Back at the Spellman home, Zelda is perplexed because the Satanic Bible does not speak of the world being destroyed and remade into a Hell on Earth. Sabrina responds that the Dark Lord wants us to serve him so He kept the truth from them. Sabrina says that the world and not just Greendale is at stake. Zelda vows to protect Sabrina at all costs. Sabrina wonders if her father knew.
Zelda takes offense that Sabrina is insinuating that her father connived with the Dark Lord. Sabrina responds that the Dark Lord needed her because she was a girl who represented the two tribes. Sabrina says that the Dark Lord wants to rule over witches and humankind and suggests that is why her father married her mother. Zelda vows to not let Sabrina be the Dark Lord's Queen.
Ambrose returns with the Demonicon and says that he has found the Melmoth spell. He explains that involves carving a sigil into her soul provided she constantly worries. Lilith warns them that nobody can run from the Dark Lord. Sabrina asks "Ms Wardwell" is she is here to do more of her master’s bidding. Sabrina tells her family that “Ms Wardwell” has been plotting with the Dark Lord. When Zelda asks how "Ms Wardwell" got past the onions, she explains that she does not have the same aversion to onions that the Dark Lord has.
Lilith tells Sabrina to come along but her aunts and Ambrose threaten to fight back. Lilith reveals that she is not a witch. Sabrina deduces that "Ms Wardwell" is actually Lilith and that Lilith killed her favourite teacher and has been posing as her in order to serve the Dark Lord. Lilith reiterates the Dark Lord's demands and warns that the Dark Lord will destroy everything and everyone in his path should she resist.
Sabrina acquiesces despite her family's protests. She says that she needs answers about her father and mother. Hilda warns Sabrina that she will be like a lamb led to the slaughter. Ambrose volunteers to go with her but Lilith says that Sabrina can only take her familiar Salem.
At Dorian Gray's Room, Father Blackwood bends the knee to the Dark Lord and pledges fealty. The Dark Lord orders him to rise and give a report about the Church of Night. Blackwood tells the Dark Lord that he has brought the church back to the "old ways" and renamed it the Church of Judas. The Dark Lord inquires about Sabrina but Blackwood struggles to answer. He tells the Dark Lord that Sabrina is dangerous but the Dark Lord disagrees that Sabrina is too dangerous for the High Priest of Judas.
Father Blackwood says he tried his best but the Dark Lord orders him to be silent, causing the fire to roar. The Dark Lord tells Blackwood that he is no Judas. The Dark Lord reminds Blackwood that the Church of Judas like all the other covens exists to exalt Him and now Sabrina Spellman. He orders Blackwood and his flock to report to Sabrina and to bow to her.
Blackwood scoffs but Lucifer warns him not to question him. He orders that Sabrina's coronation and all attending festivities will be held at the Academy of Unseen Arts. He orders Blackwood and his coven to accommodate them. He then dismisses Blackwood and Prudence.
Meanwhile, Roz asks Harvey how they will stop the gates of Hell from opening. Harvey tells her that his dad has a lot of dynamite for controlled explosions. Theo replies assuming we can find them. Roz reassures her friends that she has the Cunning and that she has been practising. Harvey tells his friends to grab everything they need. The three set out with guns.
At the Academy, Lilith tells Sabrina that the Dark Lord won't be long and that he will want everything to be perfect. Sabrina recalls her role as Lilith in the passion play and asks Lilith why she doesn't bend to the Dark Lord and asks why she does his bidding. Lilith explains that she promised to serve Him faithfully in return for Lucifer lifting her up and make her Queen of Hell. Lilith admits she believed him but tells Sabrina she doesn’t understand.
Lilith explains that the Dark Lord was kind and gentle at first. She reveals that Greendale is built on the site of where the Dark Lord first fell to Earth. Sabrina asks if that is why Greendale is so messed up. Lilith explains that Greendale is a nexus and a cursed place. When Sabrina asks what happened next, Sabrina explains that the Dark Lord turned into a dark, horned creature after the fall of humanity. Sabrina asks why she still serves the Dark Lord. Lilith replies that is all she ever knew. Sabrina dismisses her for being weak.
Dorian interrupts to tell them that the Dark Lord is read. Lilith leads Sabrina into Dorian Gray's Room. The Dark Lord welcomes Sabrina and her familiar Salem. She asks what he wants from her. The Dark Lord demands respect and love but settles for gratitude. Sabrina asks why she should be grateful to him. The Dark Lord says that he gave her beauty, strength, and power above all other mortals. Sabrina replies that she did not ask for those things or want them.
The Dark Lord replies that he knows she if lying and tells her that the truth is that she loved the power He had given her. He compliments Sabrina for her wrath and describes her as the fit consort He has been waiting for millennia. When Sabrina suggests Lilith, the Dark Lord responds that Lilith knows that her purpose is to serve. He tells Sabrina that her purpose is to blow the Horn of Gabriel for Him, opening the Gates of the Pit for the aristocracy of Hell to attend her coronation. He tells her that she will wear the Crown, sit on the throne, and remake the world in Hell’s image once they have danced the Mephisto Waltz. He vows that all the demonic hordes will be freed and that the two of them will reign over Hell on Earth for all eternity.
Sabrina replies that she has school. The Dark Lord laughs and reminds her that she said no every step of the way and yet here they are. He tells Sabrina that the Path of Night is her only path and that every choice that she has made has led her here. He says that He has made quite sure of that and reveals that Nick Scratch has helped advance his plan. Nick appears and tells Sabrina that the Dark Lord told him to befriend her but admits that he fell in love with him.
Sabrina spits in his face. Nick says that he would never hurt her but that he did not know he was advancing the Dark Lord’s agenda. Sabrina is angry but the Dark Lord tells her not to blame him because it wasn't his choice. He tells them that there is no such thing as choice and that there is only His desire. Sabrina asks if her father conspired with the Dark Lord but the Dark Lord reveals that Edward Spellman is not her father.
Sabrina experiences a flashback to the vision of the twins and her father offering her to the Dark Lord. The Dark Lord tells Sabrina to submit and to blow Gabriel's Horn at sundown in the clearing where she signed her book. Sabrina flees and Nick tries to stop her. Salem hisses at Nick. The Dark Lord tells Nick to leave her be and that his work is done. Meanwhile, Harvey, Theo, and Roz enter Tunnel 13. Roz touches Sabrina's mural and seizes a vision of the Gates. She says she can lead them to the Gates.
Father Blackwood gives an embellished account of his meeting with the Dark Lord and claims that the Dark Lord proclaimed his coven as the one true church of darkness. The coven hails Satan and tells the coven to take part in an unholy communion. The witches and warlocks steps forward to drink the wine. Agatha and Dorcas obey orders to step forward as Blackwood shouts Hail Satan.
Sabrina returns home with Salem and breaks the news to her family. Sabrina asks if her father Edward would offer up her mother Diana to the Dark Lord. Zelda says that Edward loved Diana and would never do that. Hilda says that might be true. Ambrose and Zelda react with shock but Hilda reminds Zelda that she was Diana's midwife. Hilda tells Sabrina that her mother struggled to produce a child so that she and Edward went to the Dark Lord who blessed them with a child. Hilda then recalls that Diana came to her and was worried about Sabrina because she thought that the baby wasn't Edward's. Zelda is shocked and asked why the Dark Lord would do such a thing.
Ambrose explains that he has read apocryphal books on Satanic lore and that the Dark Lord perverts the Holy Trinity by siring a babe of witch, mortal, and infernal blood. He deduces this was part of the Dark Lord's plan to instigate the apocalypse. As the rain pours down, Sabrina realizes that the Dark Lord tricked her father and used her mother and that He now expects her to fall in line. Sabrina vows to defy Satan and says that she will always be a Spellman. She vows to fight the Dark Lord but admits she doesn't know how. Lilith returns and says she has an idea about how to fight the Dark Lord.
Meanwhile, Roz leads her friends to the Gates of Hell. Theo doesn't think that dynamite will work. Harvey asks Roz to do her cunning vision. Roz approaches the Gate and touches it with her hand. Roz is overwhelmed until Harvey shakes her out. Roz says she saw runes and symbols on the gate and thinks that these will keep them locked, likening it to a protection spell. Harvey realizes that they can draw paintings to keep the Hordes of Hell of bay. He asks Roz if she can help. Roz tells him she can help and transfers her powers to him. Harvey rapidly draws several symbols while Theo pastes them against the gate.
Back at the Spellman house, Zelda questions why they should trust Lilith. Lilith responds that Sabrina's defiance has given her hope that her story isn't finished. Sabrina says that Lilith is at least being honest. Lilith proposes that they join forces to "gut the bastard." Hilda asks how they can defeat the Dark Lord since he is god. Lilith points out that the Dark Lord has never been a god but is merely a fallen angel, a creature of the cosmos. While the Dark Lord is powerfully ageless, she reassures them that she has seen Satan bleed. She tells them that she knows his weak spots if they wish to listen.
Sabrina asks how. Lilith explains that Sabrina is powerless which will work to her advantage. She tells Sabrina that her family is her secret weapon. Lilith explains that the Dark Lord is expecting her at the woods alone. Lilith reassures Sabrina that she won’t be alone and unarmed. She asks if anyone here knows how to smelt. They turn to Ambrose, who welds a blade of pure iron. Lilith says the blade won't kill the Dark Lord but will distract him and that they have to do exactly as she says.
In the woods, Lilith tells Sabrina to exploit the Dark Lord's greatest weakness: his arrogance, pride, and ego. She tells Sabrina to flatter the Dark Lord and be in his thrall. She tells Sabrina to keep him facing her at all times. Lilith explains that the Dark Lord has two wounds on his back which have never fully healed, where his wings were ripped from His body. Lilith’s plan involves Sabrina trapping his foot with a horseshoe so that her aunts can stab him in the back with daggers forged in Megiddo, where Christianity was born.
The Spellmans carry out Lilith's plan but the Dark Lord reveals that only the Spear of Longinus can kill him. He points the daggers at Zelda and Hilda's neck and throws Ambrose to the ground. The Dark Lord forces Sabrina to pick up Gabriel’s Horn in return for sparing the lives of her aunts. Sabrina grabs the horn from that altar and blows Gabriel’s Horn.
Meanwhile in the mines, Theo, Harvey, and Roz hear screams and rumbling. The Devil says that the damnation game begins. He warns Sabrina not to defy him again and tells the Spellmans they are expected at her coronation. Ambrose asks now what. Sabrina says that we pray that Harvey, Theo and Roz are nowhere near the Gates right now.
Back at Tunnel 13, the three friends realize that the Gates of Hell are opening. Harvey proposes running but Theo thinks they don't have enough sigils. Theo tries to block the gap of the gates but is almost grabbed by the demonic horde. Harvey and Roz free him. Theo asks if the sigils will work and if Roz's cunning is right.
Back at the Spellman household, Lilith apologizes for the failure of their plot and says that she has been sent by the Dark Lord to prepare Sabrina for the ball. Lilith tells Sabrina she will make a wonderful queen. However, Sabrina says that the fight is not over and that she has been looking through the spell books on ways to fight the Dark Lord. She tells Lilith that she has been reading her father's journals. Sabrina says that Edward Spellman is more her father than the Dark Lord. Lilith leaves to prepare the demonic aristocracy. Sabrina tells Salem that she will find a way.
Meanwhile, Prudence asks her father if they are going somewhere. Father Blackwood tells her to pack a suitcase for the twins and to bring only necessities. Prudence asks why they should run from the Dark Lord. Blackwood angrily responds that the Dark Lord will raise that "brat" above them all. He vows not to bow down to a Spellman whore and tells her that the four of them in this room are the only ones who matter now. Blackwood says they are leaving Greendale tonight.
When Prudence asks about the rest of the Coven, Blackwood reveals that he has poisoned them at Communion. Prudence is horrified and tries to leave but Blackwood warns that leaving him now means leaving the twins forever. Prudence takes one last look at her half-siblings and vows to kill her father wherever he goes. She returns to the Desecrated Church to find Agatha and Dorcas choking on poison.
She teleports herself and the other Weird Sisters to the Spellman household. Prudence begs Zelda, Hilda, and Ambrose to help her sisters and reveals that Blackwood poisoned the entire Coven. She tells Zelda that they are still alive and are at the Desecrated Church. While Hilda and Prudence attend to the Weird Sisters, Zelda and Ambrose teleport themselves to the Desecrated Church. She tells Ambrose they will save as many of them as they can. They start with Melvin and Elspeth.
Meanwhile, Lilith finds Harvey, Roz, and Theo have succeeded in using the sigils to hold back the demonic hordes. Lilith is pleased with the mortals for keeping the Gates of Hell from opening. Back at the Spellman household, Ambrose asks Prudence how her sisters are. Prudence thanks Hilda for saving their lives. Ambrose tells Prudence that Father Blackwood used them by exploiting their desire for a father. He says that Blackwood blinded them to the family that they already have. The two hold hands.
Meanwhile, Sabrina reads one of her father's journals and finds the Acheron Configuration that held Batibat. She considers using it to trap the Dark Lord. Nick says he can help and appears in her room. Sabrina tells him to leave but Nick begs for her forgiveness and says that he could not disobey the Dark Lord's commands. Nick says that he truly loved her and that the Dark Lord only ordered him to track her later. Nick affirms his love for Sabrina, but she says that she cannot trust him again.
Nick pleads with Sabrina to let him help her. Nick thinks that the Acheron Configuration can be used to trap the Dark Lord since it is based on the most sacred and complex bindings in nature, the human body. He explains that her father was inspired by Leonardo da Vinci's sketch of the Vitruvian man but that Acheron is only as strong as the magic and binding spell behind it. He says it is not something she can do alone. Sabrina is encouraged by the arrival of Harvey, Roz, Theo, and Lilith.
Lilith says that against all odds there remains a hope in Hell. Sabrina says she will need everybody's help. She tells Nick to fix the Acheron Configuration as amends. She tells her friends that they will proceed with a "glamour to end all glamours." She tells Lilith to trick the Dark Lord into thinking that everything is going according to plan.
At the throne room, the Dark Lord asks where are his guests. Lilith claims that the aristocrats of Hell and Sabrina are awaiting her word. Lilith arranges a treat for Satan with a woman wearing the blindfold singing a song. She is followed by several masked dancers and singers, who sing a song for the Dark Lord. One of the dancers is Sabrina who takes of her mask.
The Dark Lord leads Sabrina to her throne while Lilith presents her crown to the Dark Lord. The Dark Lord crowns Sabrina. He names her as Sabrina Morningstar, Proud Lady of Pandemonium, Maiden of Shadows, and Queen of Hell. The guest shout a toast to Satan and Sabrina.
The Dark Lord and Sabrina dance the Mephisto's Waltz. During the dance, Sabrina flatters the Dark Lord and asks if she can address him as dad. He tells her to address him by his formal titles. Sabrina asks the Dark Lord to give her Greendale as her own. The Dark Lord grants her wish. The guests begin chanting in Latin before removing their masks, revealing themselves as the Spellmans and Sabrina's mortal friends.
The Dark Lord is angry at her defiance but Sabrina replies she is a Spellman first. Ambrose throws the Acheron Configuration, trapping the Dark Lord inside. Nick tells her well-played while Zelda says that Edward would have been proud. However, the Dark Lord breaks his way out of the Acheron Configuration and shouts that no prison can contain him.
Lilith restrains the Dark Lord and tells him that they need a prison. Nick says there is no stronger prison than the Acheron Configuration but Lilith responds that the human body created by the "False God" is the best prison for the Dark Lord. Sabrina volunteers but Nick instead volunteers in her place. He tells Sabrina that she taught him how to love and traps the Dark Lord in his body.
The demon-possessed Nick tries to attack Sabrina but is knocked to the ground. Ambrose restrains Nick with a sleeping spell. Lilith leads Sabrina and the others with the demon-possessed Nick to the Gates of Hell. Lilith vows to take good care of Nick and convinces Sabrina to relinquish her crown, making herself Queen of Hell.
Queen Lilith bestows two gifts on Sabrina. For her first gift, she restores Sabrina's witch powers and tells her not to give them up. When Theo asks about the second gift, she respond they will soon find out. Harvey carries the demon possessed Nick to Lilith, who carries him through the Gates of Hell. Sabrina rubs her head against the Gates of Hell and weeps for Nick.
Back at the Academy, Ambrose and Prudence embark on a quest to hunt down Father Blackwood. Before leaving, Prudence beheads Blackwood’s statue. She tells Ambrose that her father won’t be easy to hunt down and to kill. Ambrose vows to seek his true destiny as a witch, something shared by Prudence.
Meanwhile, Zelda tells Hilda that only a handful of witches and warlocks have survived Blackwood's mass poisoning. Hilda asks what they should do since they don’t have a Dark Lord to worship anymore. Zelda says that they are now the Church of Lilith and that as High Priestess she will figure it out.
At Cerberus Books, Sabrina meets up with her mortal friends. Sabrina tells them that all her life she believed that she was half-witch, half-mortal but that she has realized that she is something else. Theo asks her what she is going to do. Sabrina says that she doesn't know but will figure it out including finding out about her mother's side of the family. Sabrina thanks her friends for saving the world and says they can work together against the forces of Satan.
Theo thinks they are like a club now. Harvey proposes the name Fright Club. Shortly later, the real Ms. Wardwell enters the shop and tells them that she woke up from the most vivid and incredible dream. She recalls seeing the Night of the Living Dead but that she is famished. Sabrina realizes that this is her second present from Lilith. Sabrina tells her mortal friends of her mission. Salem meows, prompting Sabrina to call her group five. She tells them that her mission is to go to Hell and get her boyfriend back.
- The Mephisto Waltzes are four waltzes composed by Franz Liszt from 1859 to 1885.
- Mephisto or Mephistopheles is one of the chief demons of German literary tradition.
- Luke Cook, who plays Lucifer Morningstar, also played Dorian Gray in The Librarians.
- Sabrina, her friends, and her family, perform the song Masquerade from Phantom of the Opera.