"Demoncism" is the twelfth episode of the third season of Star vs. the Forces of Evil.

It premiered on November 8, 2017, alongside "Sophomore Slump".[1]


Star and Tom's friendship is put to the test when Tom decides to get rid of his demons.[2]


At Butterfly Castle, Star tries calling Tom on her compact mirror to follow up on the corn shake get-together they planned in "Club Snubbed", but she can't get in touch with him. When Pony Head appears at her door covered in nervous sweat, Star asks her what's going on, and she reveals that Tom is secretly getting a "demoncism" to remove the demons inside his body. In addition, preparations are being made for Tom's demoncism that very moment, and Pony Head doesn't know where it's being held.

Star and Pony Head go to Pony Head's ex-boyfriend Seahorse, who also got demoncized and now works as a nerdy sales clerk at a compact mirror store. They try to ask him where Tom's demoncism is being held, but he acts robotic and only talks about the store's selection of compact mirrors. Pony Head is heartbroken that Seahorse doesn't even seem to recognize her, but Star eventually tricks him into giving them a map to the demoncism site.

That night, Star and Pony Head follow the map to where dozens of cult-like people wearing cloaks have gathered together to carry out Tom's demoncism. As Pony Head distracts them, Star finds Tom in a nearby tent and tries to convince him not to go through with the ritual. Tom says he genuinely wants to do it; inspired by Star's recent efforts to be a better princess, he wants to be a better prince. Star gets angry at Tom for going to such extremes to change himself, but Tom gets angry in return and refuses to change his mind. Star exits the tent in frustration and leaves with Pony Head.

The head demoncist begins the ceremony, and Tom is chained to an X-shaped table. As a strange liquid is smeared on Tom's face and the cultists begin chanting, Tom starts screaming and writhing in agony, and the area becomes engulfed in blue flames. Meanwhile, Star takes her frustration out on some trees when she notices the flames nearby. When she sees the cloaked cultists fleeing the area, she returns to the site of Tom's demoncism and sees him struggling in pain. Unable to undo his chains with her magic, Star climbs onto the table and holds him close.

Some time later, Tom wakes up in the tent bed with Star by his bedside. The head demoncist enters holding a tiny demon in a jar, saying the demoncism was a success. While Tom is glad to be free of his demonic rage, the demoncist says that demon is only one of several thousands that still inhabit Tom's body, and it will take years of demoncisms before all of them are removed. Tom is miserable at the thought of being an evil demon for the rest of his life, but Star tells him he can improve himself without the demoncisms as long as he's willing to try. With Star's support, Tom decides that the pain of expelling the demons inside him isn't worth it.

Star and Tom leave the site together, and Star asks if he still wants to get a corn shake, to which Tom says yes. When they meet back up with Pony Head in the forest, she notices them holding hands.


Major characters

Minor characters

Production notes



View the episode transcript here.


S3E12 Star and Tom walking together with pinwheels
Click here to view the gallery.


Revelations and continuity

  • Star mentions getting corn shakes with Tom, which they talked about in "Club Snubbed".
  • Tom is revealed to have thousands of little demons inside his body that are responsible for his anger. Only one is removed during his demoncism, and he chooses to deal with his anger issues with the rest still inside rather than remove them.


  1. Disney XD Animation (2017-09-30). Get ready for November, friends!. Tumblr. Retrieved on 2017 September 30.
  2. November 2017 Programming Highlights for Disney Channel, Disney XD and Disney Junior. Disney XD Press (2017-10-30). Retrieved on 2017 October 30.

Start a Discussion Discussions about Demoncism

  • Thoughts on Demoncism

    5 messages
    • This episode was really good. honestly the scene where Star holds and comforts Tom is one of the most emotionally powerful scenes i've s...
    • When you put it that way...