6. Herb Baumeister
A group of young gay men disappear in Indiana during the 1990s. An amateur detective uncovers clues that leads to identify a merciless offender.
Latest episode
S2 E10 · Mark Goudeau
Unknown Serial Killers of America is a documentary TV series that premiered on Oxygen on May 18, 2025. It has 2 seasons and 16 episodes so far and is still airing new episodes. The latest episode, Season 2 Episode 10 "Mark Goudeau", aired on October 11, 2026.
Explores the chilling cases of lesser-known serial killers whose crimes went unnoticed for years, leaving a trail of fear and unsolved murders before they were finally caught.
Last updated
16 episodes · 2 seasons
2025 · 6 episodes · Last episode: 1 year ago
A group of young gay men disappear in Indiana during the 1990s. An amateur detective uncovers clues that leads to identify a merciless offender.
From 2001 the bodies of 12 black women start to surface in Missouri and Illinois. As the investigation intensifies the killer start to taunts authorities.
Multiple unidentified bodies are found inside barrels in a New Hampshire forest. Decades later, a murder 3,000 miles away reveals their connection to a serial predator who changes his identity after every violent kill.
Five corpses are found on the Florida hog trails. The investigation stalls until two men narrowly escape the perp's clutches. Years later, eight more bodies are found in nearby woods, leaving police to wonder if it's the same evil killer.
In the '90s, a deranged killer stalks sex workers in Riverside, Calif., claiming the lives of 13 women. When a would-be victim describes the perp to police, the race is on to catch the murderous john before he strikes again.
Chilling confessions from a vicious slasher detail only some of his 100+ victims. When he's set to be the first serial killer ever released from prison, an eyewitness from decades prior could force justice on the man who vows to kill again.
2026 · 10 episodes · Last episode: 4 weeks ago
As Phoenix faces a severe wave of violence, detectives must simultaneously hunt down two deadly predators—a rapist turned murderer and a random sniper—as the city plunges into fear and the body count rises
Young women are brutally murdered on both sides of the Savannah River, leaving investigators searching desperately for clues until a surviving victim manages to escape and expose the predator hiding as a suburban father
Bodies of gay men appear along I-95, each marked by the same chilling signature. Investigators connect the murders and reveal a serial killer who slips across state lines. As panic grows, the FBI tries to corner the predator before he strikes again.
After a series of victims are found in upstate New York, posed and stabbed beyond recognition, police pursue a maniacal suspect seemingly unable to control a compulsive urge to kill.
After a young mother of two is found murdered and posed at a truck stop, investigators launch a desperate manhunt for a long-haul trucker whose killing spree leaves a trail of victims across state lines.
When police discover the chilling connection of a slaughtered mother and daughter to a convicted murderer, they go on a hunt across state lines to stop a calculating maniacal killer methodically checking victims off his deadly list.
When police discover a string of deaths at an upscale retirement community are not natural, they uncover a predator with a motive that defies reason and end up exposing what could be one of the most prolific serial killers in American history.
After a killer dumps bodies along Miami's Tamiami Trail, delivering a chilling message scrawled on a victim's back, a rising body count fuels a desperate hunt -- until one woman's daring escape exposes the predator hiding in plain sight.
When a series of brutal attacks on young women terrorizes the Twin Cities, detectives are taunted by a killer who repeatedly calls 911 to confess - forcing investigators into a desperate race to stop him before he kills again.
When four women are found murdered across four states in a single month, police race to track down a charismatic drifter whose charm conceals what experts believe is a deadly rage toward women.
A date for the next episode of Unknown Serial Killers of America hasn't been announced yet. Follow Unknown Serial Killers of America in the Streambay app and you'll be notified as soon as a new episode airs.
The most recent episode of Unknown Serial Killers of America, Season 2 Episode 10 "Mark Goudeau", aired on October 11, 2026.
Unknown Serial Killers of America has 2 seasons with 16 episodes in total.
Unknown Serial Killers of America first aired on Oxygen on May 18, 2025.
Download the Streambay app, follow Unknown Serial Killers of America, and you'll get a push notification the moment each new episode is released.
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Unknown Serial Killers of America
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