Homer then pokes Cthulhu's head with a trident, and his ink spells the title of the episode and the opening credits.

The segment begins at the underwater base of Mapple, where Steve Mobbs (on a screen) tells about the new Myphone and the new unfunny version of himself to an excited audience.

After a sleepover at Milhouse's, he, Nelson, and Bart find themselves in a cell, trapped by Lisa, suffering from dissociative identity disorder (similar to James McAvoy's character from Split), who closes them in again after they do not ask for an encore on her performance.

Visitors and Mr. Burns are killed by the elders, Agnes Skinner as a Ludodactylus eats off Principal Skinner's arm, Jasper as a Dilophosaurus bites off Kirk Van Houten's head, and the Simpson family are threatened by Grandpa and Jacqueline Bouvier (turned into an Indominus rex-like theropod and a Parasaurolophus respectively).

In the end, the Simpson family escape alive and unharmed, though their helicopter is being flown on the back of the transformed Agnes.

Tony Sokol of Den of Geek gave the episode 3 out of 5 points ranking, stating "Ultimately this is a disappointing Halloween installment, not horrifyingly though.

The series has been edging closer to the "clever" side of humor over the irreverently silly, and the laughs are increasingly muted.

Club gave the episode a C+ ranking, stating "It’s tempting after a dully serviceable outing like this to say it’s time to bury the ‘Treehouse of Horror’ concept as an unnecessary annual disappointment.

"[3] Jesse Schedeen of IGN gave the episode a 5.6 out of 10 points ranking, stating "It almost never feels like there's enough room for the writers to really take advantage of these horror parodies.