Established after the Bolsheviks took power in 1919, the gulags were forced labor camps where at least 1 million people died over the next 50 years.

Jack Unterweger went to prison for murder, then found fame as an author — before strangling several women to death in Austria and Los Angeles between 1990 and 1991.

The enormous ocean sunfish known as the Mola mola can grow to be 5,000 pounds and 14 feet long, making it the world's largest bony fish.

Velma Barfield was a sweet God-fearing grandmother. Unfortunately, everyone in her life seemed to die mysteriously.

This is the story of Linda Kasabian, the Manson Family's getaway driver who would ultimately be the woman responsible for Charles Manson's downfall.

While Juneteenth began as a local celebration of Texas' last slaves being freed on June 19, 1865, it has since evolved into a worldwide celebration of freedom.

How lies and gross negligence contributed to the Space Shuttle Challenger disaster, one of the worst disasters in NASA's history.

Before Marilyn Monroe, there was Norma Jeane Mortenson: a curly-haired brunette who never imagined she would be more than a housewife.

Also known as the robber crab and terrestrial hermit crab, the Indo-Pacific coconut crab reigns supreme as the largest arthropod on Earth.

"Black Wall Street" was once the United States' wealthiest African-American neighborhood. But during the Tulsa Race Massacre of 1921, a white mob destroyed the whole thing in just one day.

Drawn together by shared childhood trauma, Henry Lee Lucas and Ottis Toole became lovers — then serial killers who terrorized America in the 1970s.