Jimmy was the head of a gang called the “25” Club which consisted of hoodlums who resolved to be rich by the time they were 25. Jimmy stole some bonds of his father’s behind his father’s back and when Tracy recovered them, Jimmy was afraid Tracy would find out about his criminal behavior. He tricks Junior into joining the club and tricks him into robbing stores around town, telling Junior after the first job that he is a criminal now and he has no choice. Junior turned the tables on Jimmy by stealing back the the money and recruiting Pat Patton to go undercover and prove his innocence. Jimmy and his club was quickly arrested after this.
Later, Jimmy’s bail was paid by Jean Penfield who was writing a book on the criminal underworld and wanted to interview Jimmy. He instead stole the manuscript and took it to Big Boy who was infuriated that it incriminated him. He ordered for Jean to be killed. Jimmy tried once with a car bomb but failed. He then tried to abduct her by jumping in the car with her. The two struggled for the wheel and crashed into a gasoline tanker. Jean survived but Jimmy didn’t.