Landon Warfield: You know, I would really enjoy putting a bullet through your pretty little head, but we talked about that, remember? Killing's too quick, I want you to suffer. No no no, not like that, not physical suffering... Oh you're good, real good. You don't even seem to care about yourself. But you gotta have a husband, gotta have a boyfriend... or maybe a girlfriend. Jess Mastriani. We even have her address.
Agent Nicole Scott: She's just my contact. We're not even friends.
Landon: Al, give the address to our friend. Tell her to go there next. Oh don't worry, it'll be quick, and then you'll have the joy of knowing you're responsible for her death for the rest of your life, however long I decide that might be.
Agent Nicole Scott: She's just my contact. We're not even friends.
Landon: Al, give the address to our friend. Tell her to go there next. Oh don't worry, it'll be quick, and then you'll have the joy of knowing you're responsible for her death for the rest of your life, however long I decide that might be.
— "Deep Cover"
Jessica "Jess" Mastriani and the FBI's Missing Person's Task Force have solved many kidnappings, murders, and mysterious disappearances in their careers, but a special few of the criminals they face stand out for their despicable cruelty.
All spoilers are unmarked. You Have Been Warned!
Season 1
- "M.I.A.": Quino Salazar is a Bolivian drug kingpin who seeks to expand his empire to America. To do this, Quino tricks desperate women into coming to America as his unwitting drug mules, then forces them to work in his drug fronts. Should any of the women fail him in any way, Quino brutally kills them, stabbing one of the women and burning another alive when Richard Crowley steals some of his product. By the time the FBI cottons on to his operation, Quino has trafficked a dozen women into his service and has enough drugs to begin a drug war.
- "White Whale": Charles Edward Denton, a literary professor, is in truth the Triple B Killer, having killed six people in Delaware with the horrific modus operandi of "bind, burn, butcher" before he was caught by Agent Brooke Haslett. Upon being released from prison, Denton begins killing again, decapitating his ex-wife, blowing up an agent who investigated him, and even tricking his own daughter into helping him kidnap Jess. When this fails, Denton kidnaps Brooke's friend Sunny Estrada, attaching her to a bomb and tormenting her with the knowledge that she doesn't know when she'll die. When Brooke arrives, Denton tells her that she can either kill him and thus kill Sunny, or save Sunny and let him escape, all to make him her "white whale".
Season 2
- "The Last Stop": Louis Proctor, after being hired by "Charlie" for a bank heist, goes rogue with his crew to track down his boss. After beating the man he thinks is Charlie until he's hospitalized, Louis's crew then hijacks the bus he's on, beating everyone onboard for information before locking them all in a storage crate to die. After learning that he might have put his money in a diner, Louis kills two of the diner's workers before kidnapping four of the passengers; to force Charlie to show himself, Louis threatens to shoot all four of them, one of whom is a pregnant woman going into labor.
- "In The Midnight Hour": Randall Markham is a bank robber and Assistant Director John Pollock's Arch-Enemy. Markham's MO has him create "distractions" for his heists, at least one of which killed four people when he set a mall on fire. In preparation for his most ambitious heist yet, Markham pulls a hit and run that puts a man in a coma; leads a dozen agents into a bomb trap; and kills and butchers his own girlfriend Julie before butchering the ME and her driver as well. Even when caught, his only regret is that he didn't turn Julie "inside out".
- "Cop Out": Jack Sanderson is the Chief of the Ridgeport, Connecticut PD. In truth the biggest criminal in the city, Sanderson's precinct is a den of corruption, skimming goods and money from the city's port and beating or killing any witnesses to their crimes; Sanderson also kills good cops in his precinct, pinning the murders on a deceased killer. While pretending to be an ally to the FBI, Sanderson murders his own deputy chief to obstruct the investigation, then forces an innocent cop to kill Jess in cold blood, even taking it step by step when she's hesitant to do so.
- "Puzzle Box": The man known only as "Captain America" is a Chinese human trafficker and slaver with thousands of victims. After smuggling Chinese immigrants to America, the man then ransoms them to their families; when the victim is ransomed, the man takes advantage of their illegal status to force them to work for him in his sweatshops, killing them when they can no longer work. When he learns a reporter is investigating him, the man goes to her location and threatens to kill every woman in the room unless she shows herself.
- "Deep Cover": Landon Warfield is a powerful Arms Dealer whom Agent Nicole Scott investigated in the past. Resurfacing in the present day following his previous defeat, Landon decides to make everyone who targeted him suffer by killing their loved ones, with as many as fifty potential victims on his list. After kidnapping Carrie Marx to make her uncle create a passport for his assassin, Landon begins his crusade, with victims dropping like flies. Though originally loving with Nicole, as soon as he learns of her status as an agent, Landon adds her to his list, having his assassin target Jess with sadistic relish before attempting to make her watch him kill Carrie.
- "Paper Anniversary": Jeffrey Harrington is a former fashion magnate who, after being divorced by his wife for having an affair, decided to never be "rejected" again. Targeting emotionally vulnerable women and brainwashing them into believing that only he could ever love them, Harrington creates a harem of loyal "wives", purposefully producing children that he can groom into his security force. Harrington also refuses to let the women leave, murdering one who did so before telling the others the outside world killed them to further brainwash them; when Elizabeth leaves anyway, Harrington tracks her down and has her brutally kidnapped back to him.
Season 3
- "Patient X": Dr. Susan Reynolds poses as a benevolent therapist, when in truth she's a self-described sadist. In her status as a school counselor, Reynolds emotionally abused troubled teen Mike Holstrom until he brings a gun to school and fires it; after helping him escape, Reynolds then slit his wrists so he would die slowly. Reynolds then kidnaps Rachel Cole and slowly drains her of her blood while begging her to describe how much pain she's in, threatening to tear out her veins when Nicole and Jess confront her.
