On July 16, 2011, more than 60 people came to 17-year-old Tyler Hadley's house and partied for hours — unaware that his parents' corpses were hidden just behind their bedroom door.At 1:15 p.m. on July 16, 2011, Tyler Hadley, a 17-year-old living in Port St. Lucie, Florida, posted a status on Facebook: “party at my crib tonight…maybe.” There was only one problem. Hadley’s parents were home. And since they’d recently grounded Hadley for drinking and drug use, they weren’t about to let their teenage son throw a party.

Members of the Hells Angels ride from San Bernardino to Bakersfield, California. 1965. Bill Ray/Contributor/Getty Images A Hells Angels biker pops a wheelie while cruising through downtown Bakersfield, California. 1965. Bill Ray/The LIFE Picture Collection/Getty Images A Hells Angels member enjoys a risky ride near Bakersfield, California. 1965. Bill Ray/The LIFE Picture Collection/Getty Images An injured member of the Hells Angels is carried out by police after getting into a brawl with security at the POP Festival in Weeley, Essex, England.

What happened on this day in history: Adolf Hitler is born, Marie and Pierre Curie isolate radium, and other important events that happened on April 20.1689: The Siege Of Derry Begins Culture Club/Getty ImagesA 17th-century depiction of the Siege of Derry. The siege of Derry begins in Ireland. Started by James II, the recently deposed King of England, the siege lasted for 105 days and pitted James’s Catholic supporters against the Crown-supporting Protestants of Derry.

What happened on this day in history: King George V changes the royal surname, Julius and Ethel Rosenberg are executed, and more events that happened on June 19th throughout history. 1846: The First Official Baseball Game Is Played The New York Mutuals play the Knickerbockers at New Jersey’s Elysian Fields in the first baseball game ever officially recorded. The Mutuals won, 23-1, over the course of four innings. Baseball grew in popularity in the decades that followed, though the first World Series would not happen until 1903.

Though historians know that Greek fire was a devastating incendiary weapon used by the Byzantines starting in the 7th century C.E., its recipe remains mysterious to this day.Greek fire was a devastating incendiary weapon used by the Byzantine Empire to defend themselves against their enemies. The Byzantine people used this 7th-century compound to repel Arab invasion for years, particularly at sea. While Greek fire wasn’t the first incendiary weapon, it was arguably the most historically significant one.