Lisa Simpson is generally known as the goody-two-shoes of the iconic cartoon family, but in the latest episode of The Simpsons’ Halloween special, she develops a murderous split personality that sees her cruelly kill a longtime character from the series . .
During the cartoon series’ latest Treehouse of Horror special — its 34th — airing Sunday, Lisa sought revenge on a character who has a long-standing grievance with her family.
The episode ends with a split-personality adult version of Lisa murdering Sideshow Bob in his prison cell.
Sideshow Bob, voiced by Frasier’s Kelsey Grammer, has been a staple of the series since Bart turned him into an authority and he swore revenge on him and his family.
The Simpsons’ Halloween special, Treehouse of Horror XXXIV, aired on Sunday and shocked fans when Lisa got revenge on a character who was a longtime enemy of the family.

Sideshow Bob, voiced by Frasier’s Kelsey Grammer, has been a staple of the series since Bart turned him into an authority and he swore revenge.
Each year, Treehouse of Horror episodes of The Simpsons air in November after Halloween and parody a famous horror film.
In 2023, the plot was titled Ei8ht, in homage to the 1995 thriller Se7en.
As the episode begins, Sideshow Bob finally achieves his long-time goal: killing Bart.
Thirty years later, Lisa becomes a university professor of criminal psychology and is tasked with tracking down a serial killer.
After discovering a series of puzzling murders, she asks Sideshow Bob for help.
He quotes a poem about Bart’s murder and Lisa tells him that when he dies in his cell, she will dance.
As she continues to discover the identity of the serial killer, she is revealed to have been the murderer all along and taken to prison.
With the help of her sister Maggie, who has become a prison guard, she waits for Sideshow Bob in his prison cell, where she reveals her split personality.

The episode ends with a seemingly adult version of Lisa murdering Sideshow Bob in his prison cell.

With the help of her sister Maggie, who has become a prison guard, she waits for Sideshow Bob in his prison cell, where she reveals her double persona.

She then explains how she used her other character, Professor Lisa, as an unwitting accomplice.

“Professor Lisa didn’t know she was my accomplice, but she’s gone now. She was my last victim. Or rather the penultimate”, she reveals
“Hello, Bob,” she said as she entered the cell, in the same menacing way he greeted Bart before all of his murder attempts.
When Sideshow Bob asks her how she got there, she replies, “I knew that if I killed enough people in the most gruesome way possible, they would send me to your prison.”
“But getting into your cell, I had a little help,” she adds, pointing to Maggie on the other side of the door.
“Lisa the Killer. I never thought you had it in you,” he replies.
“The Lisa you knew didn’t,” she said, pulling back her hair. “But I’m a different story.”
“Divided personalities? Trope alert! Call the first thought police,” he remarks ironically.

She then turns on the radio and dances while she beats him to death with a knife.

Although Sideshow Bob is undoubtedly dead after the slash festival, not everything that happens in the Treehouse of Horror series is canon.
She then explains how she used her other character, Professor Lisa, as an unwitting accomplice.
“Professor Lisa didn’t know she was my accomplice, but she’s gone now. She was my last victim. Or rather the penultimate one,” she said, turning on the radio and dancing while slashing him to death with a knife.
Although Sideshow Bob is undoubtedly dead after the slash fest, not everything that happens in the Treehouse of Horror series is canon. Therefore, Bart and Sideshow Bob are not technically dead and will continue to appear in the main series.
Sideshow Bob’s anger began in season one, episode 12, when he grew tired of being Krusty the Clown’s sidekick.
Bob accuses the clown of robbing the Kwik-E-Mart and Krusty is arrested.
However, Bart becomes suspicious and is determined to prove Krusty’s innocence.

Throughout the series, Sideshow Bob has attempted to murder Bart over a dozen times.

The Simpsons is the longest-running scripted television series. It was first established in 1989 and has now been running for 34 years. Most recently, the series was renewed until 2025
Sideshow Bob takes over Krusty’s show and invites Bart on stage during the live broadcast.
At this point, Bart puts the pieces together and exposes Bob for framing Krusty.
From that moment on, Sideshow Bob swears revenge on Bart and his family.
Throughout the series, he attempted to murder Bart over a dozen times.
The Simpsons is the longest-running scripted television series. It was first established in 1989 and has now been running for 34 years.
Most recently, the series was renewed until 2025.
This means that the series will last at least until season 36 and cross the 800 episode mark.