16-year-old Emily Sullivan's body is found in the trunk of her car, and now Benson and Stabler are investigating. It initially seems that the victim could have been killed by Agnes Linsky, a girl she had bullied. Agnes failed to get a restraining order against Emily and is near-suicidal from the bullying, giving her a motive. But DNA evidence suggests Emily was killed by her friends Brittany O'Malley, Andrea Kent, and Page Summerby; Brittany was angry at what she saw as Emily "stealing" her boyfriend. The girls tied up Emily in the car, and then Brittany tortured her to death.
In exchange for a plea deal, Brittany agrees to testify against the other girls. Andrea and Paige try an Insanity Defense that seems to be working until Novak realizes Andrea is wearing a ring that was taken from Emily's body, which seems to disprove her assertions about being horrified and in shock over the murder. She and Paige turn on each other in open court, and both are convicted. But Benson and Stabler are soon called back to the same high school, where Agnes has killed another classmate who had threatened her. Agnes tearfully says that she couldn't see a way out - even with Emily dead and the other girls in jail, the bullying just wouldn't stop.
- Alpha Bitch: Brittany
- Beta Bitch: Paige and Andrea, and presumably formerly Emily.
- Asshole Victim: It turns out to have nothing to do with her death, but Emily Sullivan was a bully who tormented another classmate.
- Axe-Crazy: Brittany is the most notable one, but Andrea and Paige too.
- Disproportionate Retribution: Brittany and her friends abducted, tortured, and ultimately murdered Emily for "cheating" with Brittany's boyfriend.
- Everyone Has Standards: Even Brittany's lawyer comments that she's "off her nut".
- Fat Girl: Agnes Linsky.
- Former Friend of Alpha Bitch: Agnes and Emily were friends as little kids, but Emily got in with the popular crowd and started picking on Agnes.
- Friendship Moment: Elliot and Olivia are visibly impressed by how quickly the jury handed out guilty verdicts, and compliment Casey on it.Elliot: That's very impressive counselor.Olivia: Remind me to give you the names of all the girls I hated in high school.
- Girl Posse: Emily, Paige, and Andrea were Brittany's.
- High School Is Hell: People will bully you nonstop, teachers and authorities either won't stop it, will join in, or will try to help and fail, and the only way out is to kill someone. Olivia and Casey talk about how much they hated their time in high school.
- Kids Are Cruel
- Murder the Hypotenuse: What Brittany thought she was doing.
- No Social Skills: Agnes
- Papa Wolf: Agnes' father is this, trying desperately for over a year to get a restraining order against Emily Sullivan. And like his daughter, he's happy Emily is dead.
- Ripped from the Headlines: Loosely based on the murder of Shanda Sharer.
- Robbing the Dead: Paige and Andrea play the role of a Guilt-Ridden Accomplice and claim that they had no choice but to follow Brittany. This might have worked...until Casey points out that Andrea (on the stand no less) is wearing Emily's ring.Casey: If you felt so bad then why are you wearing a dead girl's ring?
- Spotting the Thread: When Andrea mentions that she lured Emily out of the house by claiming they were going out to celebrate Andrea's birthday, Casey realizes Andrea's class ring doesn't match her birth month — but it does match Emily's.
- Starving Artist: Lukas is an out of work actor reduced to dressing as a bunch of grapes for a children's TV show.
- Sudden Downer Ending: Emily Sullivan is dead (and no longer a threat to Agnes), and her killers are in prison, so it's ultimately a good ending for Agnes, right? No. She has shot another bully to death, knowing that the bullying won't stop.
- Teens Are Monsters: The only decent member of the entire school seems to be Agnes, and even she succumbs to the bullying in the Bittersweet Ending. Said as much by CaseyCasey: They're monsters. They're mean, vicious little girls who think that they can do whatever they want, and up until now they've gotten away with it. But not anymore.
- With Friends Like These...: Emily - herself a horrible former friend of Agnes' - was murdered by three psychopathic teenage girls and her old best friends for "stealing" Brittany's boyfriend.
Olivia: Well, that's definitely been my experience. The people that have made me feel the worst were always my best friends.
- Discussed by Huang, who notes that girls tend to attack their own friends.
- Your Cheating Heart: Brittany thinks Emily "stole" her boyfriend, although in reality, Brittany told Lukas to ask her out as a "test" of Emily's loyalty.