Quest Red

The murder of two children sparks a manhunt that spans three decades. Plus, the National Crime Agency attempts to thwart a gun smuggling operation.

When police discover a young man's body in a Glasgow bedsit, their investigation reveals he died by arsenic poisoning. Was it murder or suicide.

When a woman's head is found in a package, police must identity and the story of her life. The case reveals bigamy, betrayal and brutal murder.

Real-life cases reveal how video evidence has been used to solve a murder. Police reveal how CCTV footage has unlocked the answer to baffling cases.

Detectives turn to CCTV footage after the shooting of an elderly man in Texas. An old pickup truck could hold the key to identifying the man's killer.

Discover how toxicologists look for clues in blood and tissue to bring murders to light, including the case of a wife poisoned by cyanide.

Discover how scientists can search beneath water for proof of homicide, with cases including a woman found floating in a pond tied to a car jack.

Follows FBI investigations into similar armed robberies across the US in which several people were killed by two male suspects.

A convicted bank robber and his partner in crime escape on their way to court and go on to make the biggest bank robbery in Wisconsin history.

Shana Grice was murdered after being stalked by her ex-boyfriend, Michael Lane. He denied involvement, but experts examine police videos to determine the truth.

Discover how toxicologists look for clues in blood and tissue to bring murders to light, including the case of a wife poisoned by cyanide.

Discover how scientists can search beneath water for proof of homicide, with cases including a woman found floating in a pond tied to a car jack.

A woman, Betty, identifies a dead body as her missing sister Annie - but Annie is still alive. A look at murderers who kill to acquire a new identity.

Wisconsin police are shocked to find an elderly couple brutally murdered in their home. When family start receiving death threats, will murder strike again.

A couple is shot in their own home but husband Dan Montecalvo survives. The investigation reveals a scheming killer who almost got away with the perfect murder.

44-year-old masseuse Larissa Macriello vanishes from her Miami apartment, and police discover a dangerous edge to her carefree lifestyle - but what is the real story.

In 1994, a 55-year-old businessman is found shot in his kitchen. The police suspect his disabled son, but would he have had the capability to carry out a murder.

Real estate developer Jana Koklich vanishes and police suspect her job led her into danger, until a local pastor comes forward with a shocking confession.

A maid finds a woman dead in Room 305 of an Oregon hotel. Her grieving husband reveals an open relationship, but was an affair to blame.

A plot to kidnap TV presenter Holly Willoughby is discovered when an undercover cop in the US spots something suspicious in an online chat room.

When investigators suspect a mother's involvement in the death of her two children, Ranger Jim Holland comes in to unearth the truth.

Emile Cilliers attempted to murder his wife, Victoria, by sabotaging her parachute on a 4,000ft skydive. Experts examine Emile's chilling police interview.