Just before New Year's, a hockey mom is gunned down at her front door; later that night, seven more bodies are found in another suburban home; police discover a shocking connection between the two crimes as they track down the killer.

After a family is found massacred inside their Santa Claus, Georgia home, the hunt for their killer hinges on the eyewitness testimony of the three young surviving daughters.

Just before Christmas, the body of a young mother is found strangled inside a burning car in a quiet Minneapolis suburb and detectives suspect that she was killed by someone very close to her.

Just after Christmas, a young couple is found murdered inside their Florida home; neighbors can't imagine the couple had been in the area long enough to make a mortal enemy; police uncover deeply personal details, and soon expose a deadly secret.

A beloved couple is found murdered inside their home on Christmas morning; a single palm print is left behind; investigators work tirelessly to match the print to a suspect, until a letter from prison takes the case on an unexpected course.

A holiday is ruined when a couple is gunned down in their bed during what looks like a brutal home invasion, but police soon discover the true motive for the double homicide is a shocking tale of deception and betrayal.

On Christmas Eve in a quiet town, elderly couple Bob and Idella Young are brutally slain at home; a bloody glove found at the crime scene has the killer's DNA, but no one matches the sample.

Two days after Christmas a mass shooting terrorizes a small town; after killing two people and wounding many more the gunman is taken into custody; when police search for answers they uncover the worst family massacre in US history.

Firefighters respond to a house fire and discover three gunshot victims inside; authorities pursue the heavily armed murderer through Christmas.

The holiday season screeches to a halt when six members of the Anderson family are discovered to have been gunned down in their home; detectives work closely with family friends to track down the shocking murderer.

The Ortega family's annual Christmas Eve party is destroyed when a man dressed as Santa, wielding handguns and a homemade flame-thrower opens fire; detectives are led down a terrifying path that leads them to a sociopath.

When a mother and her two daughters fail to show up for Christmas dinner, officers enter their home and discover all three have been shot to death; the search for their killer reveals an unthinkable family nightmare.

New Year's in a tiny town, Joanna and Carl Dutcher ring in the year with their grandson, days later, they are found violently killed; the hunt for the killer leads police to a sinister group that threatens the entire community.

A woman is shot to death while driving her sons home from a Thanksgiving celebration; the hunt for her killer leads to an unlikely suspect, making investigators realize her murder is not as random as it seems.

Earl and Terry Robertson are found brutally murdered in their home just before Thanksgiving; investigating whether this is a holiday robbery gone terribly wrong, or a crime committed by someone the couple knew and trusted.

A deranged shooter attacks a family Thanksgiving dinner, leaving four dead and even more wounded, setting off a massive holiday-season manhunt to catch the killer - before they can strike again.

Each episode of this true-crime reality series examines a different felon, usually a female, who has committed murder or attempted murder. The victim is usually the perpetrator's partner. The documentary-style series features interviews with friends and family members of the accused and victims, law-enforcement officials, attorneys and other people with first-hand knowledge of the cases.

In "She Made Me Do It," women are the supposed masterminds behind deadly acts but aren't necessarily the ones accused of the crimes. As is customary with these types of shows, witness testimony, interviews with experts and dramatic re-enactments are used to tell the story of each case. Viewers get both sides of the story in each case before finding out the jury's verdict. Romance is often at the core of the attacks.

This series delves into the psychological showdown that takes place inside actual police interrogation rooms and dissects what happens to yield a confession. Each hourlong episode takes viewers through the twists and turns of a real homicide case, from the crime scene to the suspects' questioning to the ultimate confession. The police officers and detectives assigned to each case reveal their methodology while interviews with the suspects' and victims' friends and family shed light on the crime. In every case, the interrogating officer will "break" the suspect and get a shocking reveal of what really happened.

"Killer Couples" is in the same vein of the long-running true-crime series "Snapped," which tells stories of people who commit murder or attempt murder, but with a focus on couples who commit crimes. Using re-creations and firsthand accounts, each episode digs into a case, telling the story of the couple's romance, how the relationship evolved from love to manipulation, and what ultimately led the couple to commit the crime. The stories range from teenage lovers who go on a multistate crime spree to lesbian lovers who want to eliminate one of their husbands.

"Murdered by Morning" showcases stories where individuals are unaware that the night in question will be their last. From a girls-night-out gone bad to an overnight shift at a local toy store that takes an unexpected turn, the series recounts how an average night can quickly turn into a nightmare. By examining each case step-by-step, the series combs through numerous suspects until the killer is eventually caught.

Retired NYPD Detective Kevin Gannon questions if the country's most notorious string of mysterious, accidental drownings are accidents or homicides and wonders if they could all be connected to The Smiley Face Killers.

Think "Cold Case" meets "CSI" with a bit of "Rizzoli & Isles" mixed in, then make it real. That's the formula for this unscripted procedural drama that follows two veteran female investigators as they attempt to crack murder cases that have lingered for years without answers and closure. Kelly Siegler is an attorney and former Texas prosecutor who successfully tried 68 murder cases in her 21 years on the job, including 20 capital murder death penalty cases in which she secured the death penalty in 19 of those trials. She gets help from veteran detectives, who dig into small-town murder cases that have gone unsolved for years in the hope of getting justice for the victims and their loved ones.

Telling the twisted stories of some of the most maniacal siblings in history. Through exclusive interviews and firsthand accounts, the series will delve into the evil minds of siblings who partnered together to commit some of the most heinous and sophisticated homicides.

Powerfully emotional stories tell of people who have been targets of compulsive stalkers. According to the Centers for Disease Control and Prevention, more than 6 million people in the U.S. are stalked each year, and in most instances, the stalker is someone the victim already knows. The series' hourlong episodes dramatize actual cases through visceral re-enactments and pointed testimony of victims, family members and law enforcement authorities, revealing what happens when stalkers can't have what -- or who -- they want, and stop at nothing to ensure that no one else can either. The chilling accounts probe the mechanics of an obsessive mind and the devastating impact of delusion.

There are manipulators in the midst, scheming right under everyone's noses. Even with people trusted the most, there may be something sinister lying beneath the surface -- a plot set in motion by someone close with a deadly motive. This true-crime series tells stories of actual murders committed not by strangers but by someone the victim knew, someone hiding in plain sight, or someone leading a double life. These wolves in sheep's clothing use deception as a weapon to try to get away with murder.