Malcolm Whitly AKA Malcolm Bright
A profiler who worked for the FBI before his current stint as a consultant for the NYPD, Malcolm's fascination with the criminal mind stems from living in the shadow of his father Martin's serial killer fame. As a child, Malcolm was the one who discovered his father's activities, and it was Malcolm who turned his father over to the police. He's haunted by half-suppressed memories of Martin's activities, suffering from night terrors and vivid hallucinations that further his obsession with discovering the truth behind his memories.
- Death Seeker: It's implied that Malcolm is this because of the trauma of being a serial killer's son.
- Experienced Protagonist: A veteran FBI agent and serial killer profiler who's forced out due to being reckless and charging in without backup.
- I Am Not My Father: Malcolm's driving character trait is his desire to separate himself from his father's influence.
- In the Blood: Everyone is worried that Malcolm has inherited his father's insanity, including Malcolm himself.
- Leeroy Jenkins: Malcolm has a nasty habit of running headfirst into danger.
- Repressed Memories: Malcolm has vague memories of finding a girl in a trunk and its what caused him to call the police on his father...only there is a period of time (days-weeks) between when he claimed to have found the girl and when he contacted the police. Everyone assumed that he saw photos of his father victims and the girl was a figment of his imagination as they never found her. The Junkyard Killer finally confirms her existence to the police and they open an investigation to find her.
- Sherlock Scan: As a trained profiler, Malcolm is able to read a suspect's body language to maker determinations about their lifestyles, moods, and mental processes.
The youngest of the Whitly siblings, Ainsley enjoys a successful career as a reporter for a local news network. Ainsly has hardly any memories of her father from before his arrest, and she's recently expressed an interest in reacquainting herself with "Dr. Whitly", much to her mother's horror. Ainsly is shrewd, self-assured, and confident that she'll be able to use her connection with Martin to further her own career (a sentiment her mother and brother do not share).
- Intrepid Reporter: She is a journalist who is always eager for a good story and willing to do anything to get one including visiting her father. This becomes deconstructed when her cameraman (and boyfriend) is stabbed during a lock-down and Martin performs surgery on him to save his life. He's less than pleased when he learns this as she seems more interested in the story than the fact he almost died and promptly ends things with her romantically and professionally.
A woman whose sterling reputation was ruined by the revelation that her successful and charming husband was actually a serial killer, Jessica has spent the intervening decades since Martin's arrest trying to rebuild her family name and protect her children from the legacy their father left. Though she cares deeply for her children, Jessica often oversteps boundaries in her determination to do what she feels is best for them.
- The Alcoholic: Rarely seen without a drink in her hand, though she is classy about it.
- The Atoner: She tries to channel her guilt and anger into humanitarian causes and offers a reward for any information regarding the girl in the trunk once she realizes that it wasn't just Malcolm's imagination.
- It's All My Fault: It turns out that Jessica blames herself for Martin's killing spree because she suspected he was up to something but never acted on it, because she thought he was just having an affair.
- My Beloved Smother: Jessica is an overbearing socialite who keeps pressuring Malcolm to quit his law enforcement career and get married.
Dr. Martin Whitly aka the Surgeon
A notorious serial killer known by the moniker "The Surgeon" for his precise work in disassembling his victims (skills he gained in his career as a doctor), Martin Whitly has spent years in a high security prison after his son reported him to the police. Although he's incarcerated, Dr. Whitly maintains his study of the human body, and still consults with doctors around the world on difficult surgeries. His overwhelming charisma makes him a master manipulator, and it's been implied that he was grooming his son Malcolm to take up a murderous hobby of his own.
- Even Evil Has Loved Ones: Martin is a serial killer, but still clearly loves both his children and ex-wife.
- Even Evil Has Standards: When Malcolm accuses him of having a hand in killing women in his first case with the NYPD, he expresses anger that he'd be one or that he'd help someone do it.
- Multiple-Choice Past: He mentions in "Flesh and Blood" that he became a serial killer because (maybe) his mom loved him too much (or less) or he had an abusive father. Or that he just wanted to be one.
Lt. Gil Arroyo
- Cool Car: Drives a class Ford Mustang. He's heartbroken when the roof is destroyed in "Wait & Hope" since Malcolm had to use it to improvise his safe landing.
- Reasonable Authority Figure: Allows Malcolm to join the NYPD as a paid consultant despite his rocky family ties to New York.
Det. Dani Powell
- Action Girl: In several instances, Dani gets in the action to arrest suspected serial killers.
- Get a Hold of Yourself, Man!: When Malcolm's drug trip goes bad in "The Trip" and he starts having a panic attack, Dani ultimately has to punch him and knock him out.
Det. JT Tarmell
- Accidental Misnaming: Malcolm keeps calling JT "Jaime" by mistake.
Dr. Edrisa Tanaka
- Adorkable: She's a tiny, perky, bespectacled young woman who melts around Malcolm.
- Geeky Turn-On: She's quite obviously infatuated with Malcolm, impressed by his forensic knowledge.
- Why Did It Have to Be Snakes?: Edrisa is terrified of snakes. Which is unfortunate in "Annihilator", as the killer surgically implanted several live Black Mambas in one of his victims.
- Jack the Ripoff: The antagonist of the pilot is a former patient of Martin's who became enamored of him and sought to emulate him by copying his kills.
- Freudian Excuse: The suspect went after his victim because of the need to be officially recognized as family.
- Murder-Suicide: The killer in "Annihilator" tries to do this when the police track him down, poisoning his wife and kids as well as himself. Thanks to Malcolm and Dani's intervention, he fails.
- Bad People Abuse Animals: Isaac is a 12-year-old boy who would routinely kill his pet rabbits, but his mother covered it up for him. This escalated to stabbing his own father to death. He later stabs his mom's boyfriend for not letting him go trick-or-treating.
- Enfant Terrible: The murderer in "All Souls and Sadists" is a 12-year-old boy with sadistic tendencies.