During his childhood, he was regularly teased about his mother's promiscuity. In 1942, when he was ten, she slept with a drunken US soldier. Jack stole the soldier's Zippo lighter, which he used to set alight his mother's home, trapping her and the serviceman inside. After this he vowed never to be ashamed again. Jack became something of a legend among the street kids of London.
He met Tommy when he was fifteen, when he was trying to torch a warehouse, which belonged to Ramsey. Tommy recognised the fearless ferocity in Jack, and took him under his wing, realising he would be an asset to his organisation.