Set in 1995, Satluj follows Jaswant Singh (Diljit Dosanjh), a bank director living in Amritsar with his wife, Parminder "Pammi" (Geetika Vidya Ohlyan), and their children. His life takes an unexpected turn when he learns that Bibi Gurpej Kaur Bannowal (Jyoti Dogra), the mother of his late friend Kirpal (Bhupender Singh), has mysteriously disappeared. Jaswant turns to his friend, Senior Constable Satnam Singh (Saurabh Sachdeva), for help, but Satnam dismisses the matter and urges him to stay away. Refusing to let the case go, Jaswant launches his own investigation and makes a shocking discovery: Gurpej had been declared an unclaimed body and cremated without her family's knowledge. As he digs deeper, examining crematorium records and questioning staff, Jaswant uncovers evidence of a chilling conspiracy. He finds that the Punjab Police allegedly executed innocent civilians on dubious grounds and secretly cremated them as unidentified bodies, while their families were left searching for them. Investigating just three crematoriums—in Patti, Durgiana, and Tarn Taran—he uncovers records of more than 2,000 such cases. Determined to expose the truth, Jaswant takes the evidence to court, bringing the alleged police atrocities into the public eye. At first, the authorities dismiss his claims, hoping the controversy will fade. But when Jaswant refuses to back down and the movement gathers momentum, those in power retaliate with drastic measures. What follows is the gripping remainder of Satluj.