Lord Lucan
Few people today are familiar with Lord Lucan's name. The 7th Earl of Lucan, whose full name was Richard John Bingham, enjoyed some notoriety in the UK during his lifetime. Rumor has it that before Sean Connery was cast as James Bond, he was a contender.
He wasn't destined to be the next James Bond for no reason. It was the 1950s, long after the Wild West had also made it a feasible possibility, and before the internet had made it an actual option for some people. The man drove an Aston Martin and abandoned his full-time job to become a professional gambler. The main problem with his choice was that he was a terrible gambler and lost much more money than he won. He owed perhaps around £250,000 in debts.
Eventually, Bingham's wife took their children and left him. Bingham reportedly lost his head and began spying on his ex, recording phone calls, and acting generally in a creepy odd manner. When his ex-girlfriend Veronica Duncan and her nanny were attacked in their house, everything came to a head. Duncan recognized Bingham as the killer after the nanny was murdered. After a manhunt, Bingham vanished without a trace.
Born: Richard John Bingham18 December 1934Marylebone, London, England
Disappeared: 8 November 1974 (aged 39)England