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Watch S2, EP10: Keys to a Killer for $0 Today

TV14Mark of a Serial Killer44mOxygen True Crime

In the 1990s, Louisiana is terrorized by multiple serial killers; the Zachary Police Department discovers the key to solving their cases when a pattern emerges with personal items missing from each local victim.

Original Air Date: Jun 13, 2020

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Available on demand
Fri, Apr 4, 10:07 PM
Sat, Apr 5, 11:38 PM
Sat, Apr 12, 12:31 AM
Sun, Apr 13, 2:03 AM

More episodes

S3, EP14 "The D.C. Sniper"
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S3, EP14 "The D.C. Sniper"

A serial sniper terrorizes the entire D.C. metro area by discreetly targeting random victims out in public and in plain sight.

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S1, EP1 "Posed to Kill"
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S1, EP1 "Posed to Kill"

In 1990, a serial killer terrorizes the University of Florida's campus, killing five students in under four days; the Gainesville Ripper leaves behind a crime scene where all the victims have been stabbed but the females have been posed like dolls.

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S1, EP2 "The Last Call Killer"
Upcoming

S1, EP2 "The Last Call Killer"

In New Jersey four bodies are found dismembered, bagged, and thrown in roadside garbage cans; the "Last Call Killer" hunted his victims openly in piano bars but no one suspected he could be hiding in plain sight, working as a local nurse.

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S1, EP3 "An Eye for Murder"
Upcoming

S1, EP3 "An Eye for Murder"

Dallas police discover three women murdered with their eyes surgically removed; police believe they have a deranged doctor on the loose until two rookie cops find themselves on the trail of a man with a talent for taxidermy and a hatred for women.

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S3, EP14 "The D.C. Sniper"
Ended

S3, EP14 "The D.C. Sniper"

A serial sniper terrorizes the entire D.C. metro area by discreetly targeting random victims out in public and in plain sight.

S3, EP13 "The Skull Crusher"
Ended

S3, EP13 "The Skull Crusher"

Police in Hartford, Conn., investigate a string of ruthless killings in the Asylum Hill area committed by a killer with a devastating mark that leaves his victims nearly unrecognizable.

S3, EP12 "The Bayou Strangler"
Ended

S3, EP12 "The Bayou Strangler"

When multiple victims' bodies are dumped around Louisiana's bayou area, a task force is formed to catch a killer who police believe may have strangled over 20 men.

S3, EP11 "The Monster"
Ended

S3, EP11 "The Monster"

Investigators in East Baton Rouge, La., hunt for a serial murderer who carefully carves up and cuts the bodies of his victims after death.


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"Mark of a Serial Killer" examines the disturbing behaviors of serial killers. Step into the minds of some of the worst serial killers to date as they taunt law enforcement. Some of these killers get a perverse gratification by habitually stealing mementos from murder scenes, including things like shoes, jewelry, keys, and even body parts. All of these stolen things are meant to taunt the investigators while the killers build up their notoriety. The killers often leave trademark clues behind as a way to mark something that was theirs, but the investigators often use these as clues to find them.
Starring: Alicia Rosato, Ashley Georgakopoulos, Bruce W Greene, Chester Goad, Erica Mary Gillheeney, Jennifer Giles, Matthew Atchley, Michael Justice, Neftali Hernandez, Oliver Hoig, Samuel French, Steve Eifert
Original Air Date: Jan 20, 2019
Genres: DocuseriesTV Series
Rating: TV14
Playback: HD
3 seasons available on demand
Available on

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