The phrase "notorious gangster" refers to a well-known criminal who is infamous for their involvement in organized crime and illegal activities. Full definition
Legend stars Hardy in a dual role as identical twins Reggie and Ronnie Kray, two of the most notorious gangsters in British history. (slashfilm.com)
Directed by the insanely prolific Hong Kong action veteran Wong Jing, Chasing the Dragon (China, 2017) is the filmmaker's crime epic, a historical drama that charts the rise and fall of two notorious gangsters who thrived in the rampant corruption enabled by Britain's colonial rule of Hong Kong in the 1960s. (streamondemandathome.com)
In this capacity, Fausto Tozzi played supporting roles in such internationally distributed films as The Wonders of Aladdin (1960)(as the cowardly Grand Vizier), Constantine and the Cross (1961), The Agony and the Ecstacy (1965)(as one of the foremen overseeing the Vatican projects of Michelangelo), The Valachi Papers (1972)(as notorious gangster Albert Anastasia), Crazy Joe (1974) and March or Die (1977). (rottentomatoes.com)