Hauntingly Familiar: Investigators must overturn a shocking decision before they can solve the hauntingly familiar murder of a teenager.

Police investigate the gruesome murder of a mother and child, only to realize all the evidence indicates the killer was someone the victims knew and trusted.

A beautiful young woman turns up savagely murdered in a bar parking lot; as investigators retrace her last known steps, several suspects with possible motives come on their radar.

Police wonder if a young woman's personalized license plate, FLRT 12, makes her the target for murder or if a far more sinister plot is behind the crime.

Police find a giant sword bent in half, alongside a victim who has been savagely murdered. Investigators must sort through the details of his complicated life in order bring his killer to justice.

After a loving mother is murdered inside her own home, police focus on their two best clues -- a blood-stained hammer and a dusty footprint.

Veteran journalist Paula Zahn steps out of the studio and into the field to unravel criminal investigations, tracking the drama of each story by featuring the opinions of those closest to the case.

An unidentified woman is found callously murdered in an off-campus apartment; police have no leads on the case until her terrified neighbour shares a chilling story.

The baffling murder of a young woman leads police to two potential suspects: her new boyfriend and an obsessed stalker.

The search for the man who murdered a single mother might lead police to the perpetrator of a second brutal crime with chilling similarities.

A college student disappears, and her family launches a desperate investigation to find her; what they discover changes their lives forever.

A murdered teenager's body mysteriously turns up in the rural Iowa countryside. Will the smallest clue be the key to bringing her killer to justice?

As police try to solve a disturbing homicide, each step of the investigation reveals another layer in a spiderweb of tragedy.

A young mother vanishes, leaving behind nothing but puzzling clues and disturbing questions; a needle in the mud may reveal the truth behind her disappearance.

Paula Zahn talks to investigators, witnesses, victims' families and incarcerated criminals.