In the decades-long runs they have enjoyed; the Law & Order franchises have given us more than a fair share of truly terrifying villains. There are probably no other shows in the American canon that have made more people afraid to leave their homes. Yet, we still watch and love them, and new installments are even being made. Here are some of the best of the worst adversaries ever to grace the Law & Order universe.

Michael Gardner — Fred Savage (SVU)

Fred Savage- Futility L&O SVU

Michael Gardner has it all, except a grip on his masculinity: a good job, plenty of friends, a wife, and a mistress. As disturbing as it is to see Fred Savage (Wonder Years) in the role of a serial rapist and stalker, it gets worse. When Detectives Olivia Benson (Mariska Hargitay), Elliot Stabler (Christopher Meloni) and Fin Tutuola (Ice T) arrest him, he hits Benson in the face when she tells him he is being charged for rape. He continues to stalk his victims and defends himself on a violation of an order of protection charge and wins. At least Benson got a measure of comeuppance when she said of him in court, “I have certainly been hit much harder.” That is a blow to his already fragile masculinity. He also decides to defend himself on a rape charge as well, seemingly to intimidate his victim to back down. He absconds when things aren’t going his way. The only thing good about his reign of terror was that it ended.

Rafael Zapata — Jacinto Taras Riddick (SVU)

Rafael Zapata - Jacinto Taras Riddick

A big player in the Velez cartel, Rafael Zapata even rattles the normally fearless ADA Alexandra Cabot (Stephanie March). After the rape and murder of an undercover police officer and a hit on the DEA agent that arrested him, Cabot is determined to take Zapata down. Not only does he attempt to strike her, but he also threatens her mother. Even though the charges are dropped, Zapata puts a hit out on Cabot anyway because he doesn’t like her moxie. He is responsible for her relocation into the witness protection program.

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Nicole Wallace — Olivia d’Abo (Criminal Intent)

Olivia d’Abo-Criminal Intent

Played by another Wonder Years alum, Olivia d’Abo, Nicole Wallace is a beautiful and alluring spree killer, con-artist, and overall criminal mastermind, and the mongoose to Eames and Goren’s cobra. She was born in Australia and had an assumedly traumatic childhood wrought with molestation. Ironically enough, you may even be tempted to feel sorry for her, until you find out more. When she began to feel as though her husband was showing more attention to their young daughter than her, Wallace snapped the child’s neck. After the body was found, she came to America and started her criminal life afresh.

She begins a relationship with a college professor and plans to kill the dean to get the professor a better job. Detective Robert Goren (Vincent D’Onofrio) finds out about the plot and begins investigating her. She flees from justice, but Goren is never one to back down. He obsessively chases her, and she declares vengeance on him, committing more crimes along the way. She succeeds in her manipulate-Goren-at-all-costs game because she ultimately kills Goren’s brother. After Goren’s mentor and substitute father kills Wallace, he tells Goren that her last words were, “tell Bobby he was the only man I ever loved,” referring to Goren by his familial nickname. Talk about getting the last word.

Delia Wilson — Brooke Smith (SVU)

Delia Wilson — Brooke Smith-SVU

When Detectives Benson and Nick Amaro (Danny Pino) question Delia Wilson for the death of one of her escorts, they find her on her farm, feeding a baby goat with a bottle. She insists that she is just a simple matchmaker and goat farmer, and she just can’t understand why the police are closing in on her. What could they possibly want? Handmade goat’s milk soap?

But the madam was not only sex trafficking girls and blackmailing a single mother attorney with a special needs child to work for her, but she sets up Captain Cragen (Dann Florek) by putting one of her dead escorts in his bed, and frames him for her death. Conclusively, she does go to prison, but she also takes the attorney she was blackmailing, the better portion of a vice squad, and a few elected officials down with her. Part of the notoriety behind Wilson is just how deceiving looks can be. She looks and seems like a normal, Bohemian, farmer that would make hand-crafted soap, but is nothing but a cold-blooded pimp.

Mark Bruner — Ritchie Coster (Law & Order)

Mark Bruner — Ritchie Coster Law & Order

“How do guys get this sick?” asks Medical Examiner Elizabeth Rogers (Leslie Hendrix) after viewing the body of the one of the killer cab driver’s victims. A fair question. This serial killer even tangles his defense attorney in his twisted game, just because he is bored. He takes his lawyer to the cemetery where he buried his victims. Now, the lawyer can’t testify because of attorney-client privilege.

“Now this is what I call fun,” Bruner says when confronted. He doesn’t care if he lives or dies, he just wants all involved to suffer. Just for fun. When speaking of the bodies, Bruner screams maniacally to his lawyer, “they are a beautiful sight, aren’t they?” Sick, indeed.

Dr. Greg Yates — Dallas Roberts (SVU and Chicago PD)

Dr. Greg Yates — Dallas Roberts SVU

So scary, he is in the Law & Order: SVU/Chicago PD crossover.

Dr. Greg Yates is the apogee of creepiness. His biological parents saw him becoming a pint-sized serial killer and when his mother fell pregnant again, they decided to put him up for adoption to another family. His first rape and murder were of a pregnant woman in North Carolina before he left for New York City to begin a new job as a surgeon. It appears his Hippocratic oath was the only joke in his story arc. He establishes a makeshift cemetery on a beach in New York and then moves on to nurses. The only way the SVU detectives were able to catch him was because of his creepy penchant for painting his victims’ nails with green nail polish. He then proceeds to move to Chicago, kidnap, rape and murder more victims, transport them to NYC in the trunk of his car, escape prison, and repeat. This guy is so creepy that he can smell pregnancy on women, which is how he determined that Detective Amanda Rollins (Kelli Giddish) was expecting, then continues to harass and manipulate her, even asking her if she were breastfeeding her baby. The only way to stop him was a bullet.

William Lewis — Pablo Schreiber (SVU)

William Lewis — Pablo Schreiber

Pablo Schreiber (Orange is the New Black) plays a convincing psychotic villain. Most fans agree that his character, William Lewis, was the most hated and feared of the lot. He is one of the most feared because of his heinous crimes: serial rapist, murderer and all-around psychopath. He had a long and storied rap sheet that even made seasoned police officers shudder. He also once put his hand on a stove burner to prove his tolerance of pain and laughed about it.

He goes down as one of the most hated because he terrorized and attacked Detective Benson. He is caught during the act, and she is saved, but it is a frightening moment, as well as his death from a sadistic game of Russian roulette. He terrorizes seasons 14 and 15, and haunts many seasons that follow.