When Walter’s daughters accuse their stepmother of sexually abusing their ailing father, a furious legal battle ends in tragedy.

A measles outbreak delays arrests in a case involving pornographic photos taken by teens at a party. Meanwhile, Benson discovers that some kids' medical records may have been falsified after Noah gets measles; Amaro leans upsetting news about his son.

Two high-profile suspects are arrested in the takedown of an online pedophile ring following a sting operation.

Carisi opens a police investigation when his niece reports a classmate for sexual assault, and Stone learns there are no perfect witnesses when it comes to sex crimes.