Watch Dateline: The Smoking Gun

A man shot and killed two teenagers breaking into his home; he said he acted in self-defense.

A beloved dad is murdered in his garage; evidence at the crime scene leaves a puzzle for police.

A murder exposes a tangled web extending from the Pacific Northwest to the North Dakota oil patch.

Days after Lauren Giddings vanished, her body is discovered steps from her apartment.

Det. Bill Clark was investigating a disappearance when a trail of clues led him to a young film director. Clark worried that the mystery was a hoax staged by a master storyteller. Turns out the script was much darker.

A cold-blooded serial killer was lurking in the woods, stalking his next victim. As Det. Bernie Nelson investigated, puzzling evidence led him to more questions until one clue helped crack the case wide open.

Three people were shot dead in a small Texas town, including two respected prosecutors. A clue that would connect the dots remained a mystery until an eagle-eyed investigator made a stunning discovery.

When Kim Dorsey was found murdered in her bedroom, the chaotic crime scene left more questions than answers. A single out-of-place item would be the key to discovering the killer's identity if investigators could find the evidence.