Darkness Calling is the twelfth episode of Supernatural: The Animation.
Lily and her girlfriend get into an argument, and when Lily's girlfriend tries to leave, she grabs hold of her. Unknowingly, this causes her girlfriend to convulse and suddenly die. Lily is left horror-struck, and realizes it was caused by her touch.
John is driving to a location as he talks about the Baker family with Bobby over the phone. Bobby is standing in front of photographs of the Bakers, which includes Lily, Lily's parents and Lily's girlfriend. John tells Bobby that Lily's mother died in exactly the same manner as Mary Winchester did, when Lily was six months old.
The similarities between Lily and Sam drives John to believe she has special powers like Sam does. John also says that there are demonic signs going around, and believes that Yellow-Eyes is coming for Lily. Bobby is a little upset to know John is going to use her as bait.
John meets with the father outside Lily's house, and discovers Edgar was planning to go see Lily. John removes Edgar from the scene when an army of demons, led by a woman, prepare to hunt Lily down. John instructs the father to do as he's told if he wants to protect his daughter.
As John creates holy water using a water tank, Edgar tells him of the night a yellow-eyed demon entered his daughter's nursery and fed her demon blood. His wife rushed in and was subsequently set aflame. Five years ago, Edgar abandoned his daughter since she reminded him of the demon. It was fear that drove him to leave, and he now feels guilty about it.
John hands Edgar a bow gun with Palo Santo Arrows and they confront the demons guarding Lily's house. John attracts the demons' attention using a torch, scaring Edgar, who doesn't think they stand a chance. However, sprinklers start pouring holy water onto the demons, causing them immense pain. The demons smoke out of their hosts as John and Edgar move past them.
Elsewhere, the woman confronts Lily and reveals herself to be the Yellow-Eyed Demon. Lily is horrified, and tries to escape the demon. The effort proves fruitless and Yellow-Eyes tells Lily that she does not have to be afraid, because they share "the same blood". Lily disagrees, claiming she is not a demon. Yellow-Eyes questions her statement, pointing out that she had killed her roommate using her powers.
Yellow-Eyes tries to coax a distraught Lily into acknowledging her abilities, but before the demon can say more, Edgar arrives and shoots at the demon using the bow gun. John appears from the glass windows above, and bursts in with two handguns. His shots clearly injure the demon.
In retaliation, Yellow-Eyes uses telekinesis to pin John to the ceiling, and comments that he "wasn't very nice" for filling his vessel's body with bullets. Yellow-Eyes proceeds to approach Lily, still intent on taking her away, but Edgar tries to intervene, only to be thrown aside similar to John.
When Edgar demands the demon to leave his daughter alone, Yellow-Eyes approaches him and begins to suffocate him. Lily, touched by her father's concerns, attacks the demon using her right hand, but this has no effect. John, meanwhile, regains movement in his hands.
Yellow-Eyes praises Lily for her anger, only for the distraction to give John a chance to cut off the demon's arm, the one being used to harm Edgar. Lily takes hold of the demon, preparing to harm it again. Left with no other option, Yellow-Eyes smokes out of its vessel.
Freed from his bounds, Edgar tearfully promises Lily that he will never leave her again. John, confident that Lily and her father will be alright, departs, and calls Bobby. John admits using bait wouldn't have worked, and they need the Colt. Bobby promises to try and find it.
Meanwhile, Edgar tells Lily he wished there was a way he could make it up to her, and he was willing to do anything. Lily thanks him. Just then, black smoke appears from above Lily, though only Edgar notices.
Edgar hurriedly knocks Lily out of the way, leading himself to be possessed by Yellow-Eyes. The demon smiles menacingly at Lily, who is horrified. John receives a call from Lily and rushes back to her location. There, he discovers Lily had been forced to kill her father in self-defense.
Despite John's insistence that he wants to help her, even comparing her to Sam, Lily demands to be alone, having embraced the fact that she is cursed and is not meant to have friends nor family.
John departs silently as a result.