|“||We are gathered here today... to honor... the passing of... Sabrina Edwina Diana Spellman and Morningstar. Though the two girls were separate for a time, anyone who knows our Sabrina knows they've always been one and the same. Cheerleader by day... Queen of Hell by night. Though there is no death for witches, may the Maiden, Mother, and Crone, guardians of the crossroads, guide both Sabrinas... into the afterlife... for they are both daughters of Hecate... for they are both our daughters.||”|
— Zelda at Sabrina's funeral
The darkest days of the void arrive as Sabrina struggles with grief and regret. Can she summon the strength to overcome an endless cycle of destruction?
Mary Wardwell reveals that Blackwood is gone and that she’ll be leading the sermon, as she is in possession of his writings. She tells the Pilgrims of the Night Church about the Void and its arrival in Greendale.
Two days before Halloween, Sabrina and Nick, Harvey and Roz, and Theo and Robin make out at Harvey’s house while watching scary movies and discussing plans for Sabrina’s birthday in the coming days. She suggests that everyone come over to her house, watch come movies, and handout candy.
Nick walks Sabrina home and kisses her good night. He also gifts her an early birthday present. Two necklaces, one for him and one for her, each with a photo of the other’s face inside. Sabrina then invites Nick into her home, and as they passionately kiss on her bed, Sabrina Morningstar comes shattering through the mirror. With her dying breath, Morningstar warns Sabrina to stop the Void.
Blackwood can feel the electricity of the Void in the air. He commands his body to stand up and reattach his head.
After learning of Sabrina Morningstar’s death, Ambrose reports to Zelda and Hilda that the three orbs of the parallel cosmos have been consumed by the Void. And now it’s on its way to destroy them, Sabrina adds. Ambrose proposes they go to the Academy’s Observatory to see what’s happening.
Sabrina decides to stay behind while Nick and her family head to the Academy. She looks to the four Eldritch Terrors that they’ve managed to trap thus far and wonder which one can help her stop the Void. Just as she’s about to wish upon the Imp of Perverse, the Trinket Man knocks on the door. He tells her that it would’ve been unwise to wish the Void away and proposes an exchange. He gives her Pandora's Box in exchange for the Imp of the Perverse. He warns Sabrina that she has to open the box from inside the Void, and in the end, it might suck her inside along with it if she's not careful.
Sabrina writes a goodbye letter to her friends and family. Salem questions why she’s doing this. Sabrina explains that it has to be her because she’s the only one who can do it. Furthermore, she blames herself for the terrors. Sabrina then proceeds to cast a spell to open a portal through her mirror to the Void and walk through. Sabrina enters the Void, which for the most part, is a room of white nothingness, with the exception of the plants its has consumed.
Hilda, Zelda, Ambrose, Nick, Prudence, and Agatha gather in the Observatory, where a wall labeled 'the Void' has seemingly appeared out of thin air. Salem arrives moments after to inform them of Sabrina’s plan to stop the Void with Pandora’s Box. They teleport to the mortuary to find that they’re too late to stop her. They try teleporting her back by force, but the Void interferes.
The Void speaks to Sabrina and asks why she had come willingly. Sabrina reveals that she’s come to stop the Void, though all those who have come before her have failed. Sabrina questions why so many terrors and death. The Void replies that there is no life or death. Only the Void. Sabrina then opens Pandora’s Box, which appears to suck the Void inside.
Hilda, Zelda, Ambrose, and Nick head into the embalming chamber, where Sabrina Morningstar’s body lays. The plan is to pull Sabrina’s soul from the Void and place it in Morningstar’s body. This unfortunately prevents Sabrina from completely trapping the Void, leaving both her body and Pandora’s Box behind. Sabrina is upset and explains that she nearly successfully trapped the Void. Prudence then calls them back to the Observatory, where the Void wall has disappeared. They conclude that Sabrina must’ve defeated the final terror.
Sabrina and Nick sit on the steps of the Academy discussing how they’ve defeated the Eldritch Terrors and how Sabrina Morningstar lost her life. Unbeknownst to them, Lilith is eavesdropping on their conversation.
Blackwood, Judith, and Judas visit Mary at her cottage and ask for her help. So, she sews Blackwood’s head back onto his body. He tells her to keep the doors of his church open and to continue spreading the good news of the Eldritch Gospel he’s been writing.
Zelda awakens Sabrina on the morning of her birthday, as she has overslept. Sabrina comments that her alarm clock mustn’t have gone off, but when she looks over to his nightstand, the clock is nowhere to be found.
Sabrina comes downstairs, where Ambrose and Hilda wish her a happy birthday. Hilda accuses Vinegar Tom of eating her first stack of pancakes, but both Zelda and Vinegar Tom both insist that he did no such thing.
Lilith reveals to Lucifer, Caliban, and Beelzebub that Sabrina Morningstar is dead. She was killed by the Void. Lilith says that there is more, but she will only tell Lucifer if he agrees to restore her powers afterwards. Lucifer agrees, and Lilith reveals that Sabrina Morningstar died and the Spellmans are using her body as a vessel to house Sabrina Spellman’s soul. With this, Caliban urges Lucifer to kill the Spellmans and reclaim Sabrina Morningstar’s body for the royal burial she deserves. Additionally, Lilith reveals the best opportunity to strike.
Caliban and Beelzebub search for an army to take on the Spellmans. They head into the mines, where they come across Mr. Kinkle and his crew. Caliban tells them the story of the exorcism performed by the Nazarene in Gerasenes of a man possessed by a legion of demons. Beelzebub then releases a legion of fly demons to possess the miners.
Trick or treaters ring the doorbell. Sabrina grabs the bucket of candy and answers the door only to discover that the once full bowl of candy has become completely empty in a matter of seconds.
Sabrina is surrounded by her friends and family for her birthday, this includes her aunts, her cousin, Nick, Prudence, Agatha, Melvin, Roz, Harvey, Theo, and Robin. As Sabrina blows out the candles on her cake, it disappears before their eyes. A horn sounds and just outside the Spellman mortuary stands the Dark Lord and Caliban with a demon army.
Lucifer asks if it’s true that Sabrina Morningstar is dead and that Sabrina Spellman occupies her body. Sabrina admits this is true. Lucifer commands Sabrina to hand herself over. Zelda orders Sabrina to come inside, but Sabrina would rather face the threat ahead of her and agrees to go along with Lucifer willingly. He commands Sabrina to bind herself, preventing her from performing magic: "Bind my hands, tie my tongue, permit my mind to spell cast none." As Sabrina walks towards Lucifer, Ambrose ups his wand, which Caliban takes as a form of treachery and orders his legion to attack. They charge towards Sabrina. When she motions towards them, they mysteriously disappear. When his entire legion is taken, Caliban charges towards Sabrina himself, and he is sent away as well. All that remains is Mr. Kinkle, who while under the possession of a demon, charges at Sabrina too. Harvey calls out to her and tells her to wait, but Sabrina unintentionally sends him away as well. Lucifer then flees after having lost his entire army in a matter of moments.
Lucifer returns to Hell after Sabrina decimated his entire force with God-like powers. Although, as Lilith points out, her information was correct. She asks for her powers back as agreed upon. However, Lucifer is only concerned with killing Sabrina. With his back turned, Lilith takes the Spear of Longinus and stabs him in his back where his wings once were. Lucifer collapses in pain, and Lilith drinks his celestial blood.
Harvey demands that Sabrina bring his dad back, but she doesn’t know what she did or where he went. Zelda asks where she acquired this power, and Prudence wonders how long it’s been happening. However, she finds herself overwhelmed with questions and exclaims for everyone to leave her alone, causing items around the house to disappear as she does.
Lilith sits on top of Lucifer and threatens to kill him with the spear. Ultimately, she decides to banish him from the Court of Hell. She casts him out to wander the mortal realm.
Ambrose has scanned Sabrina’s body and reveals to her and Nick that her body is completely empty, essentially meaning that she’s the Void. When they sucked her soul into Sabrina Morningstar’s body, they must’ve sucked some of the Void into her as well. Sabrina starts to cry and teleports away as she doesn’t wish to hurt anyone else.
Ambrose and Nick are left with the unfortunate task of reporting Sabrina’s abandonment and the fact that she is the Void and fled to protect them. Hilda questions what they will do when they find Sabrina and what’s to prevent her from accidentally zapping them away like Harvey’s dad. Nick wants to finish what they started by trapping the Void in Pandora’s box. They do this by finding Sabrina’s real body, which Nick can track with the locket he gave her using a divination spell. Zelda mentions that he would freeze in space given the lack of atmosphere. Nick retorts that his body had been forged in the flames of Hell when he was being used as a flesh Acheron. Though, breathing outer space would be a problem. Ambrose suggests using the Weird’s body, enchanting it and turning it into an Eldritch oxygen mask.
Sabrina has teleported to the Mountains of Madness, where she has been tracked down by Blackwood, a humble servant of the terrors. Sabrina attempts to use her Void abilities, but they don’t work on him, as he is immune to its powers for the same reason Sabrina was immune to the Imp of the Perverse. He offers to help Sabrina control the Void within her and even knows the location of those she made disappear.
Two weeks later, with help from Salem, Ambrose, Roz, Prudence, and Agatha manage to track Sabrina down to the Mountain of Madness, where they first encounter Blackwood. He informs Ambrose that the mountain is a holy place, and therefore, his wand won’t work. He then invites them inside the temple to see Sabrina, who looks battered and has taken a vow of silence in service of withholding the Void. Sabrina is the only thing standing in between them and the Void. She must not move nor waver, lest the cracks tear her apart. When Ambrose begins to question Blackwood’s motives, as he clearly doesn’t care about Sabrina, Prudence, Roz, and Agatha combine their psychic abilities to get a look inside his mind. They discover that Blackwood is looking for the rest of the Void. He plans to bring it together with the Void inside Sabrina and rip it out of her, consume it and claim its power for himself. They realize that they’re sitting at a sacrificial altar and warn Sabrina, but she refuses to leave. So, the Weird Sisters try to force her to leave, which causes Sabrina to send Roz and Prudence away. Ambrose and Agatha flee with their lives. Sabrina tells him that she will see him again at the end and sends him a telepathic message.
Ambrose and Agatha report their loss to Zelda, Hilda, Harvey, Theo, and Robin. However, the trip wasn’t a complete loss. They know of Blackwood’s plan, which he intends to carry out in three days on the winter solstice. Sabrina told Ambrose via telepathy exactly when they should return to her: at the precise moment when Blackwood intends to sacrifice Sabrina, when the poles of the Earth are furthest away from the sun, and the Void is controllable. Nick then returns with Sabrina Spellman's body and Pandora’s Box, which they will use to extract the remainder of the Void from within Sabrina.
Zelda, Hilda, Ambrose, Nick, Agatha, Harvey, Theo, and Robin arrive at the Mountain of Madness in three days' time and stop Blackwood just as he is about to sacrifice Sabrina. In exchange for Sabrina, they bring him all the terrors they’ve managed to capture, from the Darkness to Pandora’s box, containing the Void. Ambrose hands over Pandora’s box, which in reality, is a mystery box rigged with gunpowder, which explodes in Blackwood’s eyes upon opening it, leaving him blind. They free Sabrina, but she explains that the sacrifice still must happen as planned. Over the last six weeks, she’s gotten a crash course on everything related to the Void from Blackwood, including how to defeat it. Blackwood wanted to drain the Void out of Sabrina into an ancient containment field. Once it was inside, Blackwood hoped he would be able to consume it himself. Blackwood also told Sabrina where to find the people she made disappear. They’re inside the Void. Zelda will have to cut Sabrina open in order to drain the Void from her and open the gateway long enough for Ambrose and Harvey to go inside it and retrieve everyone with the exception of Caliban. Sabrina also suggests taking the other Eldritch Terrors into the Void to dispose of them forever. Zelda questions how long are they supposed to keep the bloodletting of Sabrina going. She replies with as long as it takes, which could be until death. Sabrina needs Nick to go into the Void too but with Pandora’s box. Once everyone is out, he has to draw in what’s left of the Void and shut the box before he’s pulled in.
Ambrose ties an unbreakable Gordian rope around Theo and Robin. Ambrose, Nick, and Harvey will hold onto it as they venture into the Void so that they can find their way back. Nick then tells Sabrina that he loves her and gives her one last kiss before the sacrifice.
Hilda and Agatha watch over Sabrina as Zelda cuts her open to begin the bloodletting, though her blood is white, similar to the emptiness of the Void. They proceed to invoke Hecate as the sacrifice causes the portal into the Void to open. Ambrose, Harvey, and Nick proceed into the Void as Robin and Theo hold the rope. Hilda then notices a banshee standing at the doorway. As Sabrina lies on the table, she revisits every year of her life before saying goodbye to all her friends and family. Before long, Ambrose and Harvey emerge from the Void with Prudence, Roz, Mr. Kinkle, and the miners. Nick then traps the Void inside Pandora’s box. Unfortunately, they are too late. Sabrina’s blood is now scarlet red, and she has bled out completely, leaving her friends and family in tears.
Zelda, Hilda, and Ambrose hold a funeral for Sabrina Spellman and Morningstar. The entire Order of Hecate is in attendance, as well as Lilith, Harvey, Theo, and Robin. Zelda and Hilda place a flower at each of their graves and ask Hecate to guide them into the afterlife.
A statue of Sabrina now stands in the center of the Academy. Hilda informs Zelda that she and Dr. Cerberus are moving back into the mortuary, as it’s better that they stick together. Zelda then looks to Hecate and asks why she didn’t save Sabrina.
Prudence enters the dungeon with a chainsaw and cuts Blackwood’s body into several pieces and scatters his limbs to the four corners of the Earth.
Nick finds Sabrina in the afterlife, otherwise known as the sweet hereafter. Sabrina asks what he is doing there. He explains that he drowned in the Sea of Sorrows. However, all that matters now is that they’re together. Sabrina and Nick then share a kiss.
- The episode title comes from H. P. Lovecraft's 1936 American science fiction-horror novella of the same name.
- Additionally, it refers to an actual mountain within the series.