Eileen Elizabeth Sheridan was known for her association with a firm headed by  English gangsters who were the foremost perpetrators of what in the East End of London?
Kray twins Twin brothers Ronald "Ronnie" Kray (24 October 193317 March 1995) and Reginald "Reggie" Kray (24 October 19331 October 2000) were English gangsters who were the foremost perpetrators of organised crime in the East End of London during the 1950s and 1960s. With their gang, the Firm, the Krays were involved in armed robberies, arson, protection rackets, assaults and the murders of Jack "the Hat" McVitie and George Cornell.
Jack McVitie Jack D. McVitie (1932, Battersea, London – 29 October 1967, Stoke Newington, London), more commonly known as Jack the Hat, was a notorious English criminal from London of the 1950s – 1960s. He is posthumously famous for triggering the imprisonment and downfall of the Kray twins. He had acted as an enforcer and hitman with links to "The Firm", and was murdered by Reggie Kray in 1967.