Elsa Einstein was Albert Einstein's second wife as well as his first cousin — and she remained married to him despite his frequent affairs.

Starting in 1791, Alexander Hamilton had a year-long affair with Maria Reynolds. Five years later, he published "The Reynolds Pamphlet," detailing how she and her husband had extorted him.

Colleen Stan became known as the "girl in the box" after she was held prisoner by Cameron and Janice Hooker inside their California home between 1977 and 1984.

In July 1951, Mary Reeser mysteriously burned into a pile of ashes in her Florida home, but the apartment around her suffered almost no damage, leading to theories that she had spontaneously combusted.

Christopher Scarver didn't like fellow inmate Jeffrey Dahmer's sickening crimes — so on November 28, 1994, he did something about it.

One of the most calculating serial killers in British history, Graham Young started poisoning his victims when he was just 14 years old and kept a meticulous diary of his crimes.

An infamous punishment used to maintain order at sea in the 17th and 18th centuries, keelhauling was when sailors would be dragged under ships as punishment.

Operation Anthropoid, a secret plan to kill Reinhard Heydrich in 1942, was the only successful assassination of a top Nazi officer during World War II.

Literally translating to "rotting cheese," casu marzu is a traditional Sardinian pecorino made with sheep's milk — and filled with live maggots.

Tara Calico disappeared in Belen, New Mexico on September 20, 1988. A year later, two Polaroids of a tied-up woman were discovered in Florida — was it her?

Born in Plympton, Massachusetts in 1760, Deborah Sampson became a hero of the American Revolution after posing as a man to join the Continental Army.

In the late 1970s, serial killer Richard Chase murdered at least six people in Sacramento, California — and drank the blood of his victims.