V. Gunasekharan (aka Guna, Arun Vijay) is a man from Chennai who faces a heartbreaking crisis: his daughter Sana needs urgent surgery in London. With time running out, he turns to a money-laundering network, hoping to mobilize funds quickly. After wiring the money from India, the broker hands him a ₹10 note—a symbolic token that unlocks the needed funds at a London branch. Guna boards a flight to the UK, swiftly gets Sana admitted to a hospital, and meets Thomas, a hospital staffer who is deeply entangled in drug use and ready to exploit any opportunity for money.
Thomas overhears that Guna used illicit channels and hatches a plan to steal the ₹10 note. He and his criminal associates ambush Guna to rob him, but Guna fights back with skill and resolve. The confrontation draws the attention of the police, and in the scuffle, Guna accidentally punches an officer, leading to his arrest for assaulting a police officer.
In custody, Guna pleads with jailer Sandra James [Amy Jackson] to grant him one day of leave so he can sign the necessary documents for Sana’s operation. Sandra refuses, sealing his dilemma and heightening the tension.
Meanwhile, Omar Quadri [Bharath Bopanna], the ruthless head of a notorious terrorist faction, Lashkar-e-Taiba, hatches a bold plan to break out three imprisoned operatives. He hacks into the jail’s automated systems, isolate communications, jam mobile networks, disable electric fences, and unlock every cell, plunging the facility into chaos as guards scramble to regain control.
Despite the danger, Guna does not flee. Instead, he leverages his combat training, strategic mind, and intimate knowledge of prison operations to regain control, thwart the mass escape, and uncover Omar’s true objective: the riot was a diversion to free specific prisoners through an alternate route. Guna threads through the chaos and manages to intercept and capture the escapees, saving countless lives in the process.
The narrative backstory reveals that Guna once worked as a jailer in India. He had captured an inmate who attempted an escape and later discovered the man was connected to Lashkar-e-Taiba, acting on Omar’s orders. In retaliation, Omar orchestrated a bombing that killed Guna’s wife and severely injured Sana—the motive behind the London operation. The same three operatives from Omar’s list in London are identified by Guna and halted in their tracks.
Driven by fury, Omar pushes for a kitchen mutiny and presses Guna to release his men. Guna again resists, defending the kitchen staff and maintaining control over the dire situation. A British military helicopter monitoring the area is drawn into the conflict when Omar’s militants attack it, prompting a broader military response.
With time dwindling, Omar abducts Sana from the hospital and demands Guna release his men in exchange for her life. Guna agrees to the exchange, leading to a tense standoff and continuous crossfire. In the end, Guna defeats Omar and dismantles his team, securing Sana’s safety.
Days later, Guna wakes up in a hospital to find that Sana has undergone the delicate surgery successfully, a mission funded and facilitated by the British government, who honor him as a national hero for his unwavering courage and devotion to his daughter. The ordeal cements his reputation as a skilled former jailer turned protector and survivor, forever altering the course of his and Sana’s lives.
