a. Photographer who molests his pre-teen models

b. Sexual predator who tracked down his rival’s sperm donor daughters

c. Rapist who preys on women late at night on the subway

(Credit: Eric Liebowitz/NBC/Getty Images)

In a 2012 episode, Van Der Beek played a spurned ex-boyfriend who sought revenge on his college sweetheart’s husband by tracking down the young women who were a product of the man’s sperm.

(Credit: Eric Liebowitz/NBCU Photo Bank)

a. Former child porn victim who kidnaps children to star in her husband’s child porn videos

b. City councilwoman who secretly holds underage sex parties in her loft

c. Lifestyle guru who is having an affair with her own son

(Credit: Michael Parmelee/NBCU Photo Bank)

In Season 15, Arquette helps kidnap a young diabetic boy for the purpose of using him in her husband’s child pornography videos. The detectives work to track the boy down before his insulin pump fails.

(Credit: Michael Parmelee/NBC/Getty Images)

a. School janitor who tortures kids inside his supply closet

b. Florist who rapes customers while delivering bouquets

c. Prison guard who assaults female inmates

(Credit: Will Hart/NBC/Getty Images)

In a multi-episode arc starting with Season 17, Episode 22, Garrett played a corrections officer at Rikers Island who assaults female inmates in and out of prison.

(Credit: Will Hart/NBC/Getty Images)

a. Lawyer who preyed on the juvenile delinquents she represented

b. Religious zealot who killed homeless kids to “save them”

c. Piano teacher who confessed to abusing and murdering a student

(Credit: Will Hart/NBC/Getty Images)

In Season 12, Mitchell was June, a piano teacher questioned in the murder of her student. She confessed, but it turned out she was covering up for her sister. Both women had been abused by their own mother as children.

(Credit: Will Hart/NBC/Getty Images)

a. Doctor who spies on patients via a hidden camera in his exam room

b. Psychic and compulsive rapist of virgins

c. Department store Santa Claus who knocked up a teenage elf

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In Season 6, episode 18, Short played a psychic from Canada who is obsessed with raping virgins. He and his accomplice wife kidnap a virgin nun, but Stabler leans on the wife to give up her location.

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a. Surgeon who uses dating service to find his rape victims

b. Minor League baseball player with a bat fetish

c. Times Square Superman who flashes tourists

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In Season 7, episode 8, Benson went undercover on a dating service linked to three rapes and found the culprit was Cain’s surgeon.

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a. Serial killer who also raped his brother

b. Erotic novelist who’s kidnapped and assaulted by a fan

c. Trust fund kid in love with his stepsister

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In Season 4, episode 20, Somerhalder played Charlie, the son of a building super who goes on a killing spree. The sadistic killer made his male victims rape women and each other, and he also raped his own brother.

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a. A peeping Tom/musician in a Beach Boys cover band

b. Foot fetishist who collects his victim’s feet

c. Lawyer obsessed with impregnating women

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In Season 12, episode 22, Stamos was a reproductive abuser who poked holes in his condoms in order to get women pregnant. He claimed to have fathered over 47 children.

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a. Rapist who stalks his victims after assaulting them

b. “Chuckles” the pedophile birthday clown

c. Serial killer who targets women named “Winnie”

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In Season 4, episode 22, Savage played a brilliant rapist who finds ways of stalking and intimidating his victims, despite restraining orders.

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a. Perverted prank phone caller

b. Sex offender who kidnaps two children

c. Writer who has sex with his own books

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In Season 7, episode 19, Phillips played Paul Gitano, a sex offender who is released from prison and immediately kidnaps two children. He ends up killing the boy, but Benson and Stabler are able to save the girl.

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a. Photographer with sadistic fantasies

b. Leader of an underground teenage fighting ring

c. Sports anchor turned porn star

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In Season 15, episode 23, Malina played a respected photographer who indulges in very dark fantasies about underage boys.

(Credit: Getty Images)