1. D.B. Cooper
2. The Schiphol Diamond Heist
3. The Gardner Museum Robbery
4. Jack the Ripper
5. The Poisoning of Alexander Litvinenko
6. Tupac Shakur and the Notorious B.I.G.
As the East Coast–West Coast rap rivalry heated up in the 1990s, so did the rivalry between Tupac Shakur and the Notorious B.I.G. When Tupac was first shot in 1994, he claimed that the culprit was likely one of the rappers from the East Coast. According to Time, Tupac released "a number of scathing rhymes" against Biggie, "including one in which he claimed to have slept with Biggie's wife." In 1996, Tupac was shot outside the MGM Grand in Las Vegas. A few months later, Biggie was shot in Los Angeles. To this day, neither case has been closed.