Students at Westmore University gather around computers to watch a woman being raped, streaming live on the internet. When Stabler and Benson interview the university's security team, they're appalled that not one student called the cops while watching the video. The detectives find the abandoned dorm room where the rape took place, which has been wiped clean of evidence.
The video shows the rapist has a unique tattoo on his forearm. SVU identifies him as student Carol Cooper, who was expelled from school and arrested for sexual misconduct. Carl now lives just a few blocks away from campus. Stabler and Fin arrest Carl. At SVU, Carl says he belonged to a fraternity and every member has the same tattoo. Cragen thinks Stabler should start questioning the other frat brothers.
One of the frat brothers identifies the rape victim as Lizzie Harmon, a student from Julliard, who showed up at one of their parties. When the detectives head to Lizzy's apartment, they notice signs of struggle and a wall tag saying "hear no evil, see no evil" - the same tag found at the scene of the crime. Cragen and Stabler interview Lizzie's mom, who's in tears over her missing daughter. The police search surveillance footage of men going in and out of Lizzie's apartment building and flag one student, Greg Engels, who was at the same frat party where Lizzie was seen.
The campus stream picks up another video of Lizzie, tied up and pleading for help. SVU traces the video to an abandoned brownstone and realizes they've been set up. Huang points out that the brownstone is significant, because it's where Greg and his brother spent their childhood with foster parents. Also, it's the same location from which Greg's little brother Jason was abducted as a child. Huang says that after Greg's parents deaths and his brother's abduction, this type of acting out may be his way of gaining control. Shortly thereafter, Stabler gets a text from Greg saying to meet him - alone - to get Lizzie back.
Stabler meets up with Greg, who tells Stabler he won't find Lizzie until SVU finds his little brother Jason. Greg also informs Stabler that he has an accomplice watching Lizzie at all times. If they don't do what he says, Lizzie will be murdered. Greg demands that Stabler read up on all the past articles he has about Jason's abduction. Stabler tells Greg that he wants to help in Jason's case, but not this way. Greg promises he'll continue to keep Lizzie captive until Jason's case is solved. Stabler reluctantly offers to help Greg.
Fin and Cragen trace Stabler's cell phone. Meanwhile, Stabler wants Greg to imagine what Lizzie's mother is going through. As Greg begins to think about what Stabler's saying, they hear police coming their way. Stabler tells Cragen's team to back off; he has the situation handled. Greg panics and tells Stabler to go to hell. Thanks to the siege, Lizzie's dead and it's because of Stabler.
As the police arrest Greg, Stabler has some final words with him. Stabler knows Greg won't let Lizzie die, because he doesn't have that kind of evil in him. Greg fights back tears, begging Stabler to solve his brother's case. Back at SVU, Fin and Stabler begin interviewing possible witnesses from Jason's 2003 kidnapping. Each witness says they remember a kid being shoved into the back of a car, but they all figured someone else would call the cops, so they never did.
One witness talks about neighbor Miriam Penner sitting on her porch the day Jason was kidnapped. Oddly, her name was never brought up in the 2003 investigation. Greg tells Stabler that he used to babysit for Miriam until her son, Danny, passed away from leukemia. Stabler suspects Miriam may have been the kidnapper. Her car fits the description of the kidnapper's car. Stabler suspects that after Miriam spent time in the psych ward after her son's death, she headed back to her old neighborhood to take Daniel, then moved to Staten Island to start a new life and raise him as her own son.
Stabler and Benson track Miriam down at her Staten Island home to find her trying to drive off with a sedated Jason in the back seat of her car. As an ambulance leaves the scene with Jason, Stabler watches a crying Miriam being taken away by police. Stabler goes back to SVU to release Greg from custody. Now they've found Jason, it's time for Greg to lead Stabler to Lizzie.
Greg leads Stabler and police to an apartment where Lizzie is hanging out with another guy, Doug. Stabler realizes that Lizzie, Doug and Greg were all part of a setup to get SVU to solve Jason's case. Greg says the entire ordeal was worth it. Before being carted off to prison, Greg is allowed a visit with his brother. They have a tearful reunion as Stabler and Benson look on.