In the fifth episode of Anthracite, Ida violently breaks down a door, and Caleb flees the scene in a panic. A flashback transports us to Faure's younger days, when she innocently managed the storage room. It was during this time that Solal left the town, taking baby Ida with him. An intrigued Faure sneaks into the room and stumbles upon the tapes containing Caleb's footage. She becomes engrossed in watching them, ultimately turning into a believer. Faure takes up the role of a nurse, hoping to get closer to Caleb, but he rejects her advances.
Back in the present, Nurse Faure liberates Eddy from the hospital and assigns him a dangerous task - to take down Jaro. Gio, meanwhile, returns to her home to find Erwan plotting to confine her in an asylum. Fearful, she decides to move in with Romeo.
As the boys journey back, they spot Ida and halt their steps. She is visibly disgusted by Jaro and reveals their connection to him. Horrified, she flees the scene, leaving Jaro perplexed. He confronts Solal, who confesses that he never returned to investigate. Instead, he came to test Caleb for a potential bone marrow match for Ida - but Caleb turned out to be a negative match. Frustrated, Solal sought permission from Marie to approach Jaro, but she angrily sent him away.
At home, Marie tidies up Juliette's room and stumbles upon a recording. As Juliette's sweet voice fills the air, Roxane barges in, and Marie is stunned by their conversation. Suddenly, Jaro returns home to find Marie lifeless, with a haunting layer of anthracite smeared across her face. Claude, filled with grief and anger, blames Jaro and orders him to leave.
At the police station, Erwan taunts Jaro, pushing him to the brink of violence. In a fit of rage, Jaro lashes out, throwing Erwan out of the station.
Elsewhere, Ida screams as she speeds off in her car, but her mind is clouded by hallucinations, leading to a devastating crash. She awakens in the darkness, only to find herself standing on a bridge. As she prepares to leap off the edge, Caleb rushes to her side. He pleads with her to stay, but when she remains unmoved, he takes a desperate measure - pushing her off the bridge. As they hang precariously over the edge, Caleb whispers words of reason, and Ida finally snaps out of her trance. Realizing her desire to live, she scrambles back up to safety. Caleb whispers, "You're the only one who can save Jaro now."
A flashback transports us to a harrowing scene where Faure brutally rapes Caleb, leading to the birth of twins in 1997. Romeo, deeply unsettled, visits his mother and finds her in the company of the same protesters who had savagely beaten him for being gay. Urgency drives him to Hari's abode, eager to accept his offer to flee the town. However, Hari appears moody and distant, leaving Romeo perplexed.
It is then revealed that Hari's mother is none other than Nurse Faure, a woman who appears friendly on the surface. She warmly invites Romeo to stay for dinner but later orders Hari to the kitchen, revealing a venomous side. She insults Romeo, claiming that Hari is too good for him and urging him to leave. As she smokes smugly, Romeo notices that the cigarette matches the stub found in the storage room, igniting his suspicions.
Romeo departs but eavesdrops from the window, hearing Hari apologize for straying from his mission. Seizing an opportunity, Romeo sneaks back inside and searches frantically until he discovers a basement hideaway containing a notebook.
Meanwhile, Gio's son, Titouan, eagerly leads his friends to the mines to show them the masked man he had encountered. Instead, they stumble upon a bracelet inscribed with the name Malia. Jaro, homeless and desperate, heads to Romeo's house seeking refuge. There, he encounters Gio, and together they realize that all the missing persons, including Emma, vanished while near a mine entrance. Jaro's heart breaks as he suspects that the attacker deliberately killed Marie after abducting the others. Gio offers comfort, and their kiss deepens into a tender moment before Erwan interrupts with news about Malia's bracelet.
Jaro frantically calls Anais' phone, only to hear from the police that she is hospitalized, with no sign of her child. Erwan suggests waiting for cave rescue teams, but Gio and Jaro refuse to wait any longer. They plunge into a cave, finding it filled with the lifeless bodies of the missing individuals. The masked man attacks Gio, but Erwan arrives in the nick of time, forcing the killer to flee. Erwan carries the injured Gio to safety and promises to send reinforcements for Jaro. Caleb, meanwhile, coerces Ida into entering the mines to assist Jaro.
At the Faures' residence, Romeo stumbles upon the notebook, and a flashback reveals its contents. Hari writes that he is a child of the light, while his twin sister confesses that she is a child of the darkness. For every life Hari saves, she must sacrifice another. When they reach adulthood, Faure brutally forces the girl to reside in the mines forever. The episode culminates in a shocking climax: Hari shoots Romeo, and Faure orders him to dispose of the body, leaving the viewer on a cliffhanger of suspense and tragedy.
