Boss, Mammootty, a ruthless loan shark, launches a financial push into cinema by backing producer Kalabhavan Shajon Prathapa Varma to mount a new film. The arrangement sours quickly when Prathapan—an associate with a different agenda—cheats him by not repaying the money, a betrayal that sets off a deadly chain of events. Prathapan is also tied to the corrupt Police Commissioner Felix John, Siddique, whose reach and power loom over the story from the very start.
Boss refuses to be shortchanged and makes his anger felt on Prathapan’s film sets, abducting the film’s director in a show of force. In response, Prathapan sends men to finish the score with Boss, but the loan shark proves more than a match for them, defeating all comers and even turning the tables on Felix’s son Joel and on Prathapan with dark swagger. The clash escalates when Felix uses the law as a blunt instrument, filing a fake case that Prathapan’s son Adithyan has vanished and blaming Boss for it. A video later shows Adithyan alive and celebrating Holi in Nagpur with Felix’s daughter Jewel, throwing the whole accusation into chaos and setting the stage for a dramatic confrontation.
Arrested in the wake of the accusation, Boss is released only after the video evidence shakes the case. On the way home, Prathapan confronts Boss, and the truth emerges in a brutal confession: after the video aired, Boss had abducted and killed Adithyan, using Prathapan’s car and disguise to stage what looked like an accident. At Adithyan’s funeral, Felix and Prathapan circle Boss, wondering if they ever truly understood the depths of his machinations. A late-night call leads Boss to a hospital where an old man wakes from a coma—the man is his brother Ayyanar, and his return unravels a past that bleeds into the present.
Three years earlier, Boss’s life had seemed almost comfortable among a wealthy family. His adopted brother Velumurugan, a man of quiet devotion, loves Poonkuzhali, whose family resists because of caste differences. In a bold move, Boss and Ayyanar confront Poonkuzhali’s elder brother Rangan and his henchmen, convincing Poonkuzhali to marry Velumurugan. But Rangan swears revenge, joining Felix and Prathapan to settle old scores. The violence erupts as the conspirators strike at Ayyanar’s household, killing the producer who sought money and attempting to end Ayyanar’s life. Ayyanar fights back, and Rangan dies at the hands of the vengeful patriarchs, while Rangan’s brother discovers that Felix and his men have betrayed them all; he is next taken down by Felix.
The treachery proves personal and brutal as Adithyan, and his henchmen, eliminate the entire family—except Ayyanar, who is left severely injured after a brutal stabbing. The family’s tragedy travels back to the present as Felix and Prathapan piece together what Boss did and why. Yet the city’s underworld remains a dangerous stage, and Boss completes the circle by kidnapping Prathapan’s and Felix’s friend Chacko, a heavy drinker who becomes a trigger for the final reckoning. Chacko’s taunts push Felix to a violent outburst, and he kills Chacko in a rage that underscores the no-holds-barred world these men inhabit.
When Boss calls for a final showdown in his old house, the lines blur between vengeance and business. The confrontation is brutal and swift, with Boss’s men overwhelmed and Felix cornered. Ayyanar makes a lethal move, stabbing Felix to death, and Prathapan falls to Boss’s hand as the final score is settled. Left standing in the burning glow of old loyalties and fresh betrayals, Boss continues his dark business as Shylock, flanked by Balakrishna Panicker and Ganapathy, ready to tighten his grip on the city’s shadows and to preside over a new, unforgiving era of fear, power, and money. Baiju Santhosh and Hareesh Perumanna are seen in the closing movements of this ruthless scheme, cementing the story’s unsettling mood and keeping the cycle of retribution firmly in motion.
