Journalist Anand Ingalagi's book El Dorado, which detailed the events at the Kolar Gold Fields (K.G.F.) between 1951 and 2018, was banned by the Indian government, but a television news channel procures a copy and interviews him.

In 1951, government officials discovered gold ore in southern Mysore State where on the same day, Raja Rocky Krishnappa Bairya was born to a poor young woman named Shanti. Suryavardhan, a powerful crime boss and politician, who accompanied the official has them killed and leases the land for 99 years under the pretext of running Narachi, a limestone mine, but secretly establishes K.G.F. He had five associates: Rajendra Desai, who oversees the transportation of refined gold bars; Kamal, son of Suryavardhan's partner Bhargav, who is adopted by Rajendra Desai after Bhargav's death; Andrews, who oversees the gold smuggling in the Western Coast of the country; Guru Pandian, president of the in-government DYSS party; and Adheera, Suryavardhan's brother who headed the K.G.F. security. Suryavardhan suffers a strock and appoints his elder son Garuda the future heir of K.G.F. Suryavardhan expected Adheera to serve as his son's aide, but Adheera unsuccessfully attempts to assassinate Garuda. In turn, Garuda bombs Adheera's car and he is presumed dead. Suryavardhan's former associates now eye the riches of K.G.F.

Rocky arrives in Bombay as a ten-year-old on a quest for wealth and power as desired by Shanti, and begins to work for Shetty, a gold smuggler and Andrews's underboss, who competes against a Dubai-based rival Inayat Khalil. Years later, he rises in the ranks and oversees the arrival of African gold bars to the Bombay coast. Rocky's influence begins to rival Shetty's own. Andrews, who notices about Rocky offers him Bombay in return for assassinating Garuda. Rocky accepts the offer and heads to Bangalore; he meets Desai's daughter Reena, falls in love with her and pursues her to accept him, much to her step-brother Kamal's chagrin and created rivalry between Rocky and Kamal. Meanwhile, a statue inauguration is organised for luring Garuda out of K.G.F. to assassinate him. Rocky, with the help of Rajendra Desai, Andrew, Kamal and Daya try hard to assassinate Garuda, but the attempt is averted even before it begins when Rocky and the entire team is spotted by Garuda's bodyguards. Rocky witnesses the authority and power that Garuda commands. Seeing no other option to murder Garuda, Rocky journeys to K.G.F., killing a unit of Garuda's henchmen to enter. The workers in K.G.F., who were forcibly kidnapped, are subjected to inhumane conditions and treated as slaves. Rocky becomes one of them and although apathetic at first, he is moved by the cold-blooded murder of a mother and son by a guard. Rocky stealthily accesses the map of the mine in the maintenance room during a roll call and narrowly escapes death after a fellow slave sacrifices himself to save the lives of his wife and unborn child. Andrews, Kamal and Desai are misinformed about the incident and assume Rocky is killed.

Rocky engages in a fight with an entire unit of twenty-three guards, killing each one of them to rescue a blind slave they were about to brutally murder. With this act, Rocky emerges as a messiah in the slaves' eyes. He orders them to burn the guards' corpses to let Andrews's and his men know he is still alive via their informants, Kulkarni and Garuda's younger brother Virat. Garuda prepares to leave his residence to investigate the fire and missing guards. To avert this, Virat smothers Suryavardhan to death, and Garuda rushes back home. Shaken by the recent bad turn of events, Garuda orders Maa Kaali's ritual to be rescheduled from the following week to the next day, planning to kill his father's allies as soon as the ritual is complete. At night, Rocky heads unsuspected through a tunnel to the site where Garuda has decided to behead three slaves as offerings to the goddess, as Vanaram discovers that the third slave is already killed in his prison cell. Upon Garuda's arrival and sacrifice of two slaves, a concealed Rocky, who had taken the third slave's place, emerges and kills him.

Ingalagi concludes that Rocky intentionally chose KGF as the location to assassinate Garuda, so that an army of slaves would help him seize control and also indicates that this is just the beginning. The news of Garuda's murder reaches Ramika Sen, ruthless politician. Adheera, who is actually alive, plans to resurface his position in KGF. This news made the people who dreams KGF happy, including Rajendra Desai, Kamal, Andrews, Guru Pandian, Daya, Shetty and Inaayat Khalil. The film ends with Vanaram ordering his men to attack Rocky and his army.