Radha, Bagavathi Perumal, a feared gangster, teams up with his crew to hijack Your Bank — one of Chennai’s largest privately owned banks — with the quiet nod of ACP Ramachandran Ajay. The target is a colossal ₹500 crores, planned for 21 May during a Governor’s party at his residence. But on the day of the heist, Radha and his squad discover the bank is already under the grip of a mysterious operative known as Michael Jackson, also called Dark Devil, and his partner Kanmani Manju Warrier. Inside, a squad of commandos arrives only to be overwhelmed.
Dark Devil insists on a deal: help him take ₹ five thousand crores in exchange for a share, a proposal Radha and his men reluctantly accept. The mood shifts when Radha learns the true locker contents amount to ₹1,510 crores, and the plan turns murderous as Radha contemplates silencing Dark Devil. Yet Dark Devil presses his advantage, revealing a bigger target and a sharper motive.
Antony alias Anto Mahanadhi Shankar, a police constable, is pressed into service as the negotiator. Dark Devil’s seductively deceptive tactic relies on a Michael Jackson voice changer, weaving confusion for the public and media as if the pop icon himself were orchestrating the crisis. Ramachandran, furious at the subterfuge, tries to shoot Dark Devil with a sniper rifle, but Dark Devil detonates a car bomb parked near the bank, turning the standoff into a chaotic spectacle. The city’s media leaks force Dayalan, the city commissioner, to step in and assess the escalating danger.
As Dayalan surveys the bank, he uncovers explosives disguised as fire extinguishers and realizes a third team has moved into the building without Dark Devil’s knowledge. A van tracked by Kanmani is targeted and destroyed as she evades capture, destroying the route and escaping. Ramachandran orders his men to trace Kanmani, but she eliminates them and exposes Ramachandran’s involvement to Dayalan, who begins to connect the dots.
Ramachandran ultimately confesses that he and his childhood friend Shyam, the Tamil Nadu Branch Head of Your Bank, plotted the heist. He had tried to hire Dark Devil, who refused, before turning to Radha’s gang—without telling them they would be killed after the job. Through bugs planted in Dayalan’s base, Radha’s team learns of Ramachandran’s confession and joins Dark Devil’s cause. Shyam flees but is captured by Kanmani. Dayalan learns that Valavan wired and planted the explosives in the drainage and begins to pursue him, while the troubling truth emerges: Dark Devil and his crew reportedly died months earlier.
A fatal misstep for Ramachandran comes when he detonates a supposed dummy bomb, which is real, killing him in the blast. Dark Devil learns that ₹25,000 crores sit hidden in the bank’s secret chest locker and arranges a meeting with Krish, the Your Bank chairman, to finalize matters. The bank’s staff reveal a third team’s assault inside the locker before the confrontation spirals.
Krish arrives and reveals that he hired the third team, then orders the destruction of the bank’s chest with hostages inside. He also forces Dark Devil to reveal his identity, and Dark Devil discloses that he and his teammates once lived like a family. They recount a Bangkok heist where Jijo and Achara had planned to wed, only to be ambushed by Krish and Shyam, who feared exposure. Jijo and Achara were killed, while Dark Devil and Kanmani escaped, with their deaths staged to protect their real money.
Dark Devil learns of Kavin, an honest bank official, who had hoped to return money to investors. Kavin is killed by Krish, who then weaponizes the narrative to manipulate events. Dark Devil and Kanmani vow to bring Krish and the bank officials to justice. The revelation deepens as Dark Devil exposes Krish’s scheme and the broader manipulation of the mutual funds’ money.
Shyam, forced to wear a bomb vest, is delivered to Dayalan and spills everything before Kanmani’s call prompts his death. Sunil Dutta, who had been abducted from Mauritius by Dark Devil’s team and who was implicated in theft from the NSE backup server, confesses that ₹30,000 crores are tied to Krish’s schemes. A media mole helps Krish frame Dark Devil and his team as terrorists, and Dayalan is suspended amid the chaos.
Inside the bank, Dark Devil and Radha’s team unlock the secret locker, only to find the money counterfeit. In a desperate bid, Dark Devil locks Krish, Sunil Dutta, and Harsha inside the locker, and Krish’s confession video is captured as the vault explodes. Kanmani arrives aboard a fire truck loaded with RDX and threatens to detonate the hostages unless the siege ends. The commandos pause fire as Kanmani and Dark Devil, wearing masks, escape toward a boat, aided by the public.
A high-stakes chase unfolds as Dark Devil, Kanmani, and the rest of their crew push past coast guards with an M2 Browning in sight, only to be shot at and plunge into the sea. The media broadcasts the video of Dark Devil’s survival, and Dayalan’s suspension is reversed in the wake of the political and public outcry.
In a post-credits scene, Dark Devil and Kanmani fake their deaths and slip away using sea scooters to a waiting boat, settling into international waters. Dayalan and his team board a helicopter toward the ship, only to discover the ₹25,000 crores are still at large, tucked away in a perilous secret. The film closes on a tense note, with loyalties tested, empires toppled, and a fragile sense of justice hanging in the balance.
