The film begins at night in Kandahar Province, Afghanistan, where Johnny Talbot, the son of American Embassy superior Bill Talbot (Robert Forster), is engaged in a mission against the Taliban. Their helicopter is suddenly struck by a missile, leading to their capture by the Taliban. Tragically, the following morning, Johnny is burned alive.
In London, Kate Abbott (Milla Jovovich), an employee of the American Embassy, is haunted by the loss of her friends during the 9/11 attacks, which prompted her government work. Meanwhile, a shadowy figure known as Nash (Pierce Brosnan), the Watchmaker, receives a dangerous explosive — hidden in a brick and activated by a mobile phone. He plants it with sinister intent at a restaurant.
When Kate approaches Vicker's Pharmaceutical for Dr. Perry’s assistance regarding Dr. Balan, she finds herself turned away without proper authorization from the home office. Later, an embassy inspector, Paul Anderson ([Insert Actor Here]), reprimands Kate for her unauthorized investigations into Dr. Balan, while agent Maureen Crane (Angela Bassett) shows her disapproval for Kate's actions.
Despite the tension, Kate plans a birthday celebration for Bill Talbot at the restaurant with her four colleagues. However, in a shocking turn of events, Bill uses Kate's account to erase five visa applicants as revenge for what was done to Johnny in Afghanistan. As the festivities unfold, tragedy strikes when Nash activates the bomb, killing all of Kate's colleagues, the glassware owner who was wrapping the present, and numerous bystanders.
In the aftermath, Kate desperately searches through the wreckage for survivors only to encounter Nash, who nearly shoots her. But fate intervenes as the gas tank explodes, momentarily incapacitating him. As Nash hunts her down, the authorities mistakenly deem Kate responsible for the bombing.
Seeking answers, she meets with Bill in a park, but things turn deadly when he attempts to kill her, believing she is somehow complicit. In a scuffle, the gun goes off, and by accident, Kate shoots Bill, who succumbs to his injuries beside a fountain, with bystanders capturing the incident on camera. Nash arrives again, and when Kate tries to react, she discovers her gun is empty, forcing her to flee once more. Nash, meanwhile, seizes Bill's ID card, which holds a GPS tracker to locate Kate.
Desperate for assistance, Kate calls her friend Lisa ([Insert Actor Here]) to bring her supplies to St. Pancras Train Station. At the same time, Dr. Balan sets up a gas test in a building, only for Nash to obliterate it with a sniper rifle. This plan signifies a much larger terror scheme set to unfold in New York City on New Year's.
As Lisa attempts to reach St. Pancras, Nash's henchmen follow closely behind her. Concurrently, Kate finds herself embroiled in a perilous situation as Nash discovers her position via GPS. Just as Kate receives necessities from Lisa, Nash's crew closes in. A chaotic chase ensues, leading Kate into the subway, where she narrowly evades capture while Nash throws a grenade her way. In a moment of adrenaline and instinct, she stabs him with a sharp metal shard, managing a temporary escape.
Taking refuge in Bill's apartment, Kate is unexpectedly confronted by Sam (Dylan McDermott). He believes in her innocence concerning the bombing and warns her about Nash's deadly reputation. Unfortunately, their hiding place is soon discovered, leading to a bomb explosion that seemingly claims Sam’s life.
With Nash still in pursuit, Kate enacts a plan to infiltrate the embassy. Sally ([Frances de la Tour]) helps Kate by disabling the security cameras, granting her access to critical information that reveals the impending New York terrorist plot. With ingenuity, she fabricates a fake passport and manages to escape the embassy just as marines storm in.
Arriving in New York City under the guise of Amy Harrison, Kate races against time. As the countdown to midnight begins, she learns of Nash’s plan to blow up the Times Square Ball. In a tense rooftop showdown, Kate confronts Nash just as he’s about to detonate his deadly payload. A fierce battle ensues, culminating in Kate overpowering and eliminating Nash as New Year's celebrations commence.
As law enforcement arrives, Kate’s actions are recognized in thwarting the impending disaster. In an epilogue, it’s revealed that since 9/11, American law enforcement has successfully thwarted numerous terrorist plots, underscoring the relentless efforts to safeguard the nation.
