The Krays were identical twin brothers, Ronnie Kray and Reggie Kray, who became notorious gangsters in London during the 1950s and 1960s. They led the Kray twins gang, which was involved in various criminal activities, including extortion, robbery, and violence. Their influence extended into the world of London's nightlife, where they ran several clubs and were known for their connections with celebrities. The Krays were eventually arrested and convicted for murder in 1969, leading to life sentences in prison. Their story has been the subject of numerous books, films, and documentaries, highlighting their complex personalities and the criminal underworld of East London during that era.