When a janitor attacks a school coach, the SVU team connect his violent behaviour to a history of sexual abuse. They identify more victims of the same predator, including prisoner Reggie Rhodes on death row.
Danny persuades his brother-in-law to assist him take care of some mobsters he's become involved with. Elsewhere, Frank asks Erin to look into his old partner to see whether or not he is guilty of shooting someone at a strip club.
A Russian nuclear submarine disappears in American waters, putting Elizabeth in a tricky situation; Stevie ends things with her boyfriend.
The team hope their stomachs are strong enough to handle an investigation into the death of a polo player. Meanwhile, McGarrett's mother makes an unexpected visit.
A professional hit at a law firm leads Willows to suspect that the company has hired a team of assassins to eliminate anyone who knows of their activities.