In episode 6 of Dead Boy Detectives, the relationship between Niko and Jenny becomes increasingly tense, while Crystal seeks Niko's assistance in banishing a demon. Together, they visit a mysterious magic shop in search of the "Light of Heart," a black heart talisman purported to ward off harmful connections.
The shopkeeper, Tragic Mick, reluctantly shares his tragic tale with them, encouraged by Niko's persistence. Years ago, during a terrible storm at sea, a father drowned his daughter to save his own life. The gods, however, showed mercy to the child, transforming her into Sedna, the goddess of the sea. From her severed fingers, walrus' were born, including Tragic Mick and his siblings. Despite Sedna's warnings, Tragic Mick desired to experience more of the world and chose to become a human, forever trapped in the mortal realm.
Meanwhile, Crystal longs to rid her mind of David's presence, and her wish is granted. But at a cost - she loses her powers. Esther, bent on revenge against the boys, coerces Monty into luring them into the woods. Crystal keeps her loss of powers a secret from the group.
Monty approaches the trio, claiming that his ghost friend has gone missing. He leads them to an enchanted forest notorious for its dangers to ghosts. Niko opts to stay behind to comfort Jenny, leaving the others to search the woods.
During their search, they stumble upon a ghost feasting on moss. Charles and Edwin inform Monty and Crystal that once a ghost consumes this moss, they are denied any form of afterlife or reincarnation. Edwin, armed with a book of knowledge, concocts a potion to rid the ghost of the moss, but they soon realize that the creature is not of this dimension. The group splits up to investigate further.
Charles and Crystal encounter David's lingering hauntings, while Edwin and Monty find themselves discussing their feelings. Monty confesses his growing attachment to Edwin, who assures him that his feelings matter. Moved by this, Monty attempts to lead the group out of the forest. Suddenly, the cat king appears, revealing to Edwin that Monty is Esther's spy and is leading them into a trap.
Monty rushes to confront Esther, arguing against the dangerous creature she has conjured. But Esther, unmoved, transforms him back into a crow, realizing that his loyalty is wavering.
Esther then reveals herself, accompanied by a giant, spiky-toothed mushroom. She commands it to capture the ghosts for consumption. Crystal, remembering the washerwoman's advice, delves deep within herself and discovers a spiritual realm where her ancestors gather. They impart wisdom about her collective power, derived from their lineage. Empowered, Crystal confronts Esther.
Connecting with the elemental being through their shared power, Crystal frees it from Esther's control, allowing it to return to its own dimension. The giant mushroom apologizes and departs, taking Esther with it. The three friends reunite, their mystery solved.
Meanwhile, Niko and Jenny have a heart-to-heart about the recent incidents, with Jenny expressing her hope that Niko won't set her up again. Elsewhere, the Night Nurse finds herself trapped inside the belly of a sea monster. There, she meets Kashi, a man who has made a home within the fish's stomach. Kashi challenges the Night Nurse's narrow-mindedness, reminding her that everyone has a place in the world. He suggests that perhaps the boys are happier where they are and offers to ask the fish to release her. The fish obliges, and the Night Nurse learns a valuable lesson in kindness, empathy, and the importance of communication.
Just as Edwin is about to confess his feelings to Charles, the Night Nurse appears before them. Charles informs her of Edwin's technical mishap that sent him to hell, and the Night Nurse notices something odd about Edwin's form. She agrees to allow them to stay together until she returns, but a巨大生物from Hell snatches Edwin and whisks him back to the underworld, leaving them all in shock and disbelief.
