In Mobile, Ala., young mother Danniella Vian, 25, disappears into thin air; 19-year-old Holly Moore's suspicious death still raises questions four years after her body is found hanging in her closet

One young woman is found with a shotgun wound to her head shortly after moving in with her new boyfriend. Then, a couple planning their wedding are gunned down in their own backyard. Will secrets from the past explain these unimaginable deaths?

Two young brides-to-be are just beginning to plan their weddings when their dreams are tragically cut short. Can desperate calls made to 911 reveal the truth about their shocking deaths?

Two 20-year-olds suffer personal tragedies then have their own lives abruptly snuffed out. He's shot while hanging out with friends; she disappears, only to turn up dead in a staged suicide. Will their families be able to prove what really happened?

Their evenings begin as fun celebrations with friends but they end in murder. With disturbing evidence, terrifying theories, and demands for justice, can the mystery of how two young partygoers are murdered be solved?

When two young women vanish without a trace, investigators are haunted by the things they leave behind - a car with the keys still in the ignition, a pair of shoes, and a coat. They disappear with no warning. Where have they gone?

After struggles in their youth, they are setting out on new paths with new hope but then the unthinkable happens. Their horrific murders are chilling. Who would kill them in such a violent way? Did they have any idea how much danger they were in?

Two young women who dream of big success as television anchors are just embarking on their careers when their plans come to a violent end. They are murdered in their own apartments and there are no signs of forced entry. Did they know their killers?

The murders of a teenage boy who never returns home from school and a teenage girl who is ambushed as she sits in a car with friends devastate their communities. It is every parent's worst nightmare - who would kill two innocent teenagers?

A respected police officer heads home after a late shift, and a young man who has just moved into his own place relaxes after watching football. How do these routine evenings turn deadly? Were their killings cold-blooded assassinations?

They are the victims of shootings that seem senseless. Who would want them dead? Did these two young people get tangled up with the wrong crowds? And will anyone be held accountable for their murders?

A man and his dog burn to death. A chase ends in murder for a motorist.

A girl vanishes on her way home, and an entrepreneur dies after a fight.

A young Hollywood celebrity is out celebrating her birthday and another young woman enjoys a late drink with friends, just a few hours later, they both end up dead and investigators try to solve the mystery. 

They are head over heels in love with their whole lives ahead still ahead of them, but then they die suddenly under suspicious circumstances. Could the strange text messages that come from their own phones hold the clues that investigators need?

A family suspects foul play when their son drowns in a few inches of water.

A 14-year-old disappears in Aruba while on a jet ski ride with an older man; a man kidnaps a young woman from the parking lot of her boyfriend's apartment building.

Home becomes the most dangerous place on earth for two lovely young women.

The murder of billionaire couple Barry and Honey Sherman in their mansion stuns Toronto, since Barry is a pharmaceutical mogul with many enemies, but it is unclear who would kill his wife; a New York teen disappears after a mysterious road trip.

A young woman acts erratically at a restaurant and police take her into custody. They release her in the middle of the night(—)and she disappears. A soldier at Fort Hood dies after falling off a balcony. Was it an accident, suicide or murder?

A 14-year-old boy vanishes, but neighbors don't tell police what they know.

Oakley Carlson is missing and no one can find her, including her foster parents and her biological parents; a young mother leaves a bar with a man she doesn't know and ends up dead.

In an ironic twist, a woman vanishes while looking for her missing friend.

Someone snatches a baby boy from his crib, and a young mom goes missing.

A severed foot is an ominous clue in the case of a missing mother of five.

One mom is missing and another spurs a manhunt for her daughter's killer.

Sisters seek justice for their siblings - but the truth might be deadly.

A man's trip ends badly. A missing mom's search party sparks suspicion.

He seems like a great partner. But when Susan Osborne and her 14-year-old son Evan disappear, it turns out "Mr. Right" has a secret. Then, when a young man is shot in a street confrontation, all clues point to one man. Could this case be that simple?

Officers discover a high school senior's strangled body in flames weeks before graduation.

The families of two young mothers who die in suspicious circumstances search for answers. Racheyl Brinson's husband says she fell to her death while hunting, while Jessica Alva's boyfriend tells police that she hung herself.

A young woman's body is found 200 miles from home, and a retired police detective uses his podcast to crowd-source the search for her killer. And, when a young mother disappears, an old answering machine message could hold the key to finding her murderer.