The investigation into a girl's disappearance leads to a high-tech kidnapper who uses the Internet to cover his tracks; Rollins reconnects with her sister.

The SVU squad tries to keep Detective Rollins' sister safe from her abusive boyfriend when she turns up beaten and pregnant; when Rollins is forced to take drastic action, an internal affairs investigation begins.

ADA Barba finds that a friend -- with a connection to a mayoral candidate front runner -- is accused of rape.

A teenager is sexually assaulted and left for dead in an alley after attending a movie star's party; Benson is suspicious when security footage from the party goes missing.

A young boy is found wandering alone in Central Park and the search for his parents leads to startling evidence of a planned mass casualty event in the city. As the SVU works with the joint-terrorism task force to find the suspects and the motive, Lt. Benson must also convince Barba to address allegations of rape and torture the boy's mother discloses.

An investigation hits a nerve with Benson when a suspect claims his genetics causes him to commit rape.

When a young woman takes a man hostage at gunpoint, Benson makes a dangerous attempt to defuse the situation. Meanwhile, the SVU discovers the shocking motive behind the abduction.