Billy Hill and Jack'Spot' Comer were One of the most notorious Offenders in London up until the 1950s. Dramatising the violent reign of 2 of London's most notorious gangsters, Billy Hill (Leo Gregory) and Jack'Spot' Comer (Terry Stone), ONCE UPON A TIME IN LONDON charts the legendary rise and collapse of a criminal empire which continued until the mid-fifties and paved the way in its notorious Kray Twins along with The Richardsons. This really may be the story of the rise and collapse.