- Complete Monster: Mary Lou Maloney from the second and third films was just an Alpha Bitch in life, manipulating boys to her own ends. When she used two boys to become prom queen, one of them, Billy, decides to retaliate with a prank, but Mary gets killed in a freak accident. Thirty years later, her spirit awakens when a girl named Jess takes a gem out of her crown, and as a result gets killed by Mary's spirit. She later torments the main character Jess's best friend Vicki Carpenter with Hellish hallucinations before possessing her. She later kills the local priest, Buddy (also one of her old prom dates), telling him there is no God or Heaven to torture him. As it turns out Vicki was dating Billy's son Craig, and Billy was the new principal, she uses this to plan to get revenge on Billy through his son and taunts him about it. Later she kills Vicki's other friend for Monica for suspecting something is going on with Vicki. While getting ready for prom, she tries to seduce Vicki's father and kills her mother. At the prom, Mary cheats the vote by killing a boy named Josh, who's running the prom votes. Billy is forced to shoot Vicki but that just gives Mary physical form. In the rampage that follows, Mary opens a portal to the underworld and attempts to drag Craig down with her. In the next film, after escaping hell, she kills a janitor who was one of her ex boyfriends. She seduces a teenage boy named Alexander, who already has a girlfriend, and kills a teacher for giving Alexander bad grades, and puts a strain on his relationship with Sarah, and kills a guidance counselor for being suspicious. Mary later kills Ale's rival Andrew, which prompts Alex to reject Mary. In retaliation, she kills his best friend Shane and frames him. When Alex rejects Mary again, she plans to kill Sarah at the prom. When Alex rushes to save her, Mary agrees to spare her, if he goes to hell with her and be her prom king for eternity. When Sarah seemingly manages to rescue Alex, Mary gives them both a false Hope Spot before killing Sarah.
- Ear Worm: "Prom Night, everything is alright"
- Ensemble Darkhorse: Wendy
- Hollywood Homely: Jude
- Tear Jerker: The ending.
- The Woobie: Dorky yet kind of cool Slick who dies merely because he's at the wrong place at the wrong time.