It is the most successful Bollywood film ever made, it set Amitabh Bachchan on the path to silver-screen immortality and modern directors have left it well alone, but now Sholay is set for a remake.

Sascha Vijay Sippy, grandson of its producer G. P. Sippy, whose company holds the rights to the 1975 classic, has agreed a $100 million (£49.6 million) franchise deal with the Bombay production house Pritish Nandy Communications. The agreement covers a remake of the Hindi-language “curry western”, a prequel, a sequel and an animated version. Production of the four-film series will start this year.

The move comes as Ram Gopal Varma Ki Aag, an unauthorised remake, is released in Indian cinemas today. Ram Gopal Varma, the director, had to rename his film, originally entitled Ram Gopal Varma Ke Sholay, and adapt the main characters and storyline after the High Court in Delhi ruled that he had infringed copyright.

Sholay, which means fire, is the highest-grossing film in India, earning an inflation-adjusted $60 million at the box office. Taking nearly three years to make, it was a lavish production for its time and ran over budget. Initially considered a commercial flop, its popularity — driven by the performances of its leading actors — grew by word of mouth. It ran for 5½ years in one Bombay theatre and is still the Hindi film with the most prints in circulation in India.

A story about a policeman who contracts two convicts to catch the bandit who slaughtered his family, the film set new standards in Bollywood. Modelled on American spaghetti westerns, with scenes reminiscent of John Ford’s Stagecoach, it won a raucous following for its gunfights, rocky landscapes and dark humour. Audio tapes of lines spoken by Gabbar Singh, the villain played by Amjad Khan, were sold separately so that fans could learn them.

Several producers, including Mr Varma, have asked the Sippys about a remake but been rejected. Pritish Nandy, once publishing director of The Times of India, won them over. His contemporary version will be the biggest-budget film made by Bollywood, whose average budget is $1million. Headmits that it is “daunting” to remake “the flagship movie for the entire industry”.

Gaining formal consent for a remake is a big step in Bollywood, which is famed for its plagiarism. Copyright protection has always been difficult in India’s cumbersome judicial system.

There has been a tendency to rip off Hollywood scripts by switching the plot to India. However, as Bollywood goes global and Indian cinema-goers show a growing taste for Hollywood fare, the issue of copyright has been brought into focus.

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