A 9 year old child's asphyxiated body is found in a suitcase on a bus, with evidence of having been in the Everglades. The coroner found she had had a quality nose job, and been raped. Benson & Stabler find she was a regular beauty pageant contestant. A suspect's computer is found with a juvenile kidnap, rape and murder how-to, apparently perfectly legal, because created using legal age models whose images were manipulated by software to make them look much younger.
A quadruple homicide with sexual overtones is just the start of an intense rampage of killings that brings a homicide detective into the mix. As the entire squad races against time to prevent further victims, the evidence leads Tutuola and Deuthorn to a building superintendent, his two sons, and a cross to bear.
After a young boy witnesses the brutal sexual assault and murder of his stepmother, his father blocks the efforts of the detectives to question him.
A Tibetan woman who was tortured in her home country is found murdered, with her foot missing, and after an exhaustive search of potential suspects, the killer is a victim of torture himself.
Detectives Benson and Stabler are called to a crime scene – a young woman dressed in a maid's uniform has apparently committed suicide by jumping off a penthouse; however, because of the degree of sex-related bruising, they believe she might have been raped and murdered. The motive for murder is exposed when the detectives investigate a strange relationship between one of the penthouse occupants (Erik von Detten) and his grandmother (Michael Learned).
The brutal rape and subsequent death of a female motorist turns out to be an informant for the FBI acting as a cyber vigilante for catching on-line pedophiles to capture the predators. Stabler, along with the homicide detective who found the victim's husband murdered, follow the trail of evidence for the latest victim she had been tracking, leading them to the US Attorney's Office and a trip to Prague for Stabler to assist the Czech authorities when they find the kidnapped girl.
When the body of a baby girl is found inside a cooler, the detectives need to investigate just who she is, and how she got there. They soon learn that the little girl had a genetic disorder known as Tay-Sachs disease that would lead to a painful death in childhood. When the parents (Elizabeth Mitchell and Gregg Edelman) admit to having killed their daughter humanely to spare her that fate, Cabot has to prosecute them for murder, despite reservations. Taking an interest in the case, Detective Munch sits in on the trial.
A six-year-old girl critically injured (and subsequently dies) in an apparent robbery gone bad tests positive for a sexually transmitted disease, putting the detectives on the trail of the family, then the store clerk, and the son of a prominent attorney who had appeared to foil the crime. When evidence turns up that the little girl's older sister was dating the alleged sexual predator, Cabot has to work some legal magic to eradicate the deal made with the older sister for testimony.
The investigation into the rape of a comatose woman leads to a doctor (Bruce Davison) whose stem cell research is funded by a billionaire (Philip Bosco) with Parkinson's disease who is desperate for a cure. The woman's parents (Henry Woronicz and JoBeth Williams) petition for custody of the child who was intended to be harvested for stem cells, while the defense argues that their experimentation on a patient who will probably never wake up serves the greater good.
When a fifteen-year-old girl (Rachael Bella) is saved from jumping in front of a train, the SVU is called in to help her. She falsely accuses an ex-boyfriend (Billy Lush) of raping her, but when the search turns to her dysfunctional family, surprise discoveries are made. From an overly helpful father (Titus Welliver), mysterious children and a bracelet that belonged to a murder victim, the detectives unravel a plot by the girl's parents to use children as surrogates.
When the decomposing body of a sexually molested five-year-old girl is discovered, Detectives Benson and Stabler's investigation leads them to the painful reality that they are searching for a serial pedophile as they race to save the life of his latest victim. As the mother of the missing girl frantically awaits news of her daughter's whereabouts, she must reconcile with the fact that her own recent bout with addiction may have played a part in her daughter's fate.
The body of a battered young boy found in a luggage compartment of an airport shuttle bus sends the detectives to his guardian who was discovered to be a pedophile only to find his corpse in bed with his genitals removed. The subsequent investigation leads them to a travel agency specializing in exotic trips for sexual predators. Stabler is disgusted when he discovers that the man responsible for the murder and castration (Michael Hayden) is himself a child molester who killed a member of his own organization for using more coercion.
When an elderly woman breaks into an apartment, the detectives discover she had been mistreated but have to investigate with no credible information from the victim because of Alzheimer's. They discover that she had been released from a nursing home to the custody of her financially scheming son who becomes the prime suspect. However, they go back to the nursing home to find a pair of suspects, including the director who details the dangers faced by both patients and staff with her own heroics precariously standing out.
The detectives respond to a brutal rape only to have the victim taken into custody by federal agents on racketeering charges. The investigation leads them to a father-son duo who are in the federal witness protection program and an agent who appears bound and determined to protect them, regardless of consequence, so they can testify against the Russian mob.
The detectives go on the trail of a recently paroled rapist responsible for the murder of a prostitute during a raid at a men's club and are called to the scene where he was shot in self defense by his own gun. However, the murder weapon was also used in another crime while he was still in prison, leading the detectives to investigate the victim through a trail of previously unsolved cases, a spending spree and another victim.
The wife of a retired attorney, a public-health doctor, is found murdered and raped in Central Park. Her work involved contacting sexual partners of HIV patients which gives the detectives a long list of suspects. The discovery of a second body in Central Park with the same signature shifts the focus to a serial killer; however, the trail leads to a man who has no knowledge of the crimes but has a distant connection to the doctor and her husband.