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

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. Police hope surveillance videos will solve the mystery of what went terribly wrong.

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

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.

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

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.

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. Investigators wonder how these routine evenings turned deadly, and if the their killings were assassinations.

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.

They head out into the night, full of youthful life and promise, but they never come back. Clues that come from behind bars may help solve the mysteries that surround the disturbing disappearances of these two women.

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?

After struggles in their youth, two people set out on new paths with renewed hope but then the unthinkable happens. Their horrific murders spur investigator to wonder who would kill them in such a violent manner.

She is an innocent bride-to-be; he's a 6-year-old schoolboy. Both are on the road, away from home, when they disappear. When her car and body are found, will the clues lead to her murderer? And will his family ever solve the mystery of his vanishing?

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. Their families hope to prove what really happened.

Two young women are savagely murdered. One has gone fishing only to turn up beaten and drowned, and the other is a pregnant mother attacked while on the job delivering newspapers. Are strangers responsible, or are the culprits much closer to home?

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?

The body of a young musician turns up in an alley. Police learn she's been spending time with an older man. Did he play a part in her murder? And when a construction worker disappears on the job, his coworkers' accounts don't add up. What are they hiding?

A mother of three is gunned down in a church basement where she's set to teach a fitness class. Police find surveillance video showing a figure in full police body armor stalking the floor in the lead-up to the slaughter. Who is this craven killer?

Beautiful 20-year-old Shelbey Thornburgh moved to Houston, Texas, to pursue her dreams of becoming a model. One night she was found murdered in her apartment with a horrific slash across her neck, and investigators are left wondering what happened to her.

Twenty-four-year-old Lindsay Buziak was a young, beautiful realtor on the rise, but after going to meet some new clients, she was found brutally stabbed to death, and the clients disappeared without a trace.

D.J. Fickey, a 27-year-old father of three, was trying to win back his wife after she left him for another man, but then he ended up with a bullet in his head. Investigators are left to decide if it was it suicide or murder.

Street-smart Angie Barlow thought she was attending a private party in a safe, gated community. But then, she vanished without a trace, and to her family's horror, her body was discovered in a shallow grave eight months later. Who would want Angie dead?

Beautiful Roxanne Paltauf was spending the night with her boyfriend in a motel, and then she disappeared. Her boyfriend claimed she stormed off after a fight, but neither Roxanne's family or the police believed him.