By the mid-1970s, gritty, violent crime films and action films about gangsters (Bombay underworld) as well as bandits (dacoits) had become popular. The writing of Salim-Javed and acting of Amitabh Bachchan popularized the trend, with films such as "Zanjeer" and particularly "Deewaar", a crime film inspired by "Gunga Jumna" that pitted "a policeman against his brother, a gang leader based on real-life smuggler Haji Mastan" portrayed by Bachchan; "Deewaar" was described as being "absolutely key to Indian cinema" by Danny Boyle. Along with Bachchan, other actors that rode the crest of this trend include Feroz Khan,