A deer version of Marge warns her son Barti, Bart as Bambi, and Milhouse, as Thumper, about a hunter, Mr Burns. Milhouse is shot and killed while Barti and Marge run away. After his escape, Barti initially cannot find his mother, but later finds her unharmed as Homer and Lenny Leonard have killed the hunter. As they start eating him, a fairy (Maggie) appears and creates the title card.

The Simpson family are living in a flooded basement apartment when Bart tells them he's gotten a job as a tutor for Rainier Wolfcastle's wealthy family. After Rainier fires Kirk Van Houten from his household staff, Bart recommends hiring Marge, Homer, Lisa and Maggie as the family's new servants. The Wolfcastles go on vacation, leaving the Simpsons alone with their house. As they enjoying the perks of living in a rich family's home, Kirk returns and asks to be let in. Kirk reveals a hidden passageway to a basement bunker, where his family has been living. A fight breaks out between the Simpsons and Van Houtens, which soon breaks out among most of the other impoverished Springfielders. After the brawl, the Simpson family are the last ones standing in the badly damaged Wolfcastle house with a pile of corpses now in the living room.

In a parody of the 1984 horror movie A Nightmare on Elm Street, Bart is telling scary stories to Lisa and Maggie to which they hide in their parents' bedroom, interrupting an intimate moment between Homer & Marge. Having grown tired of Bart's stories, Homer starts to chop down Bart's treehouse, but gets tired and passes out after a few chops.

A thunderstorm makes the tree come to life which gets revenge on Homer by kicking him for trying to chop it. The tree then stumbles upon a drive-in cinema where he sees Groot from Guardians of the Galaxy (who is also a tree-like creature), and starts attacking and killing people for laughing at him. The tree then finds a farm where he sees a sign about people chopping down trees for Christmas. Filled with disgust, he starts touching other trees which brings them to life, as well as any wooden objects, including a wooden baseball bat. Afterwards, Homer and the citizens of Springfield (except the girls because to refuse the fight) prepare for a battle against the trees, but the trees start spreading pollen, weakening the humans and even getting Groundskeeper Willie to saw off his own arms by accident. The trees, having killed all the humans, start dancing around the statue of Jebediah Springfield, while the dead humans make a Christmas tree. Homer regains consciousness, however, he gets knocked back unconscious by the wooden bat.

Vincent Price reads a scary bedtime story to Maggie about how Bart is doing his usually pranks and mischief. He begins with each month and how he creates trouble for everyone. Before Vincent can get to December, Maggie strangles him with her Phonics frog string and presses the buttons (R-I-P) and then goes to sleep.

Sherri and Terri have a party and don't invite Lisa. they watched a cool TikTok but it kills you after 7 days then Sherri and Terri die then Milhouse says he was the bouncer at the party then he is stabbed by 8 knives grandpa watches the Tiktok, Lisa and Bart learn about Bloody Mary from Groundskeeper Willie after getting poo on valentines day, she went into the well and stayed for 7 days, then Groundskeeper Willie covered the well, Lisa then watched the TikTok does not die and becomes friends with Mopy Mary, but then she went back to the well because of Lisa's clinginess.

It then ends with a teaser for "Treehouse of Horror XXXIII" and Kang and Kodos being squeezed in last minute then the credits roll.