For decades, ufologists have claimed that extraterrestrials experiment on humans with the military's help inside a secret base underneath the Archuleta Mesa in Dulce, New Mexico.

On February 16, 1981, 19-year-old Arne Cheyenne Johnson stabbed his landlord Alan Bono to death with a pocketknife — then said the Devil made him do it.

What happened to Jimmy Hoffa, Madeleine McCann, and other victims of famous missing persons cases? Explore their mysterious disappearances and the leading theories behind them.

During a few days off from filming Furious 7, Paul Walker died at just 40 years old in a car crash in Santa Clarita, California on November 30, 2013.

From "Cannibal Holocaust" to "The Blair Witch Project," these movies were so extreme that countless people thought the onscreen carnage was real.

At 7 a.m. on January 24, 1989, Ted Bundy died via execution in the electric chair at Florida State Prison after raping and murdering dozens of victims between 1974 and 1978.

Cindy Hendy wasn't just David Parker Ray's girlfriend throughout his dozens of murders as the "Toy Box Killer" — she was also his accomplice.

Go inside the most terrifying serial killer movies of all time — and the even grislier real-life murderers who inspired them.

Inside Central Park on April 19, 1989, Matias Reyes beat and raped a jogger named Trisha Meili. A year later, five innocent teenagers would be found guilty of his crimes.

A year after Ronald DeFeo Jr. shot and killed six of his family members at 112 Ocean Avenue, the Lutz family moved in and began experiencing unexplainable hauntings that would inspire The Amityville Horror.

When police raided serial killer John Wayne Gacy's house at 8213 West Summerdale Ave. in Chicago's Norwood Park in 1978, they uncovered 29 bodies.