On a storm-lashed 4 AM morning, a troubled man named Tom Cooper arrives at a suburban home with a hammer and a plan. After forcing entry, he brutally attacks and kills the couple inside before dousing the house in flames. The violence doesn’t stop there: the film then shifts to Rachel Flynn, a divorced mother who is trying to keep her life intact for her son, Kyle. Her lawyer-friend Andy contacts her about a bitter dispute with her ex-husband Richard over their house, adding pressure to an already tense day.
Rachel’s routine is upended by a traffic-choked commute and a series of near-misses with Cooper on the road. Kyle calls to hear about his game, while Rachel juggles work obligations and reminders about deadlines. A red-light confrontation with Cooper escalates quickly. At the gas station, Rachel senses she is being followed; a clerk and a helpful bystander named Leo offer to help track Cooper’s plate, but Cooper’s ominous presence intensifies when he taunts her from the side of the road. The moment briefly shifts to fear as Cooper’s threat becomes painfully real, and Rachel realizes she may be in danger not only from him but from the way events are spiraling out of control.
Inside a diner, Andy waits for Rachel, hoping to support her, yet Cooper finds him first, masquerading as a friend. A desperate attempt to warn Andy fails as Cooper violently disables the phone connection and delivers a brutal assault, ending with Andy’s murder while the stunned diners record the horror on their phones. The encounter solidifies Cooper’s menacing reach as he continues to taunt Rachel, leaving her to navigate a path toward safety while keeping Kyle out of harm’s way.
With only minutes to spare, Rachel rents time for a plan and tries to lure Cooper toward Deborah, a client who fired her. She phones the police, hoping to corral him at Deborah’s house, but Cooper instead descends on Rachel’s own home, where Fred discovers the news about the diner murder and becomes a target himself as Cooper forces Mary into danger. The confrontation moves like a game of cat and mouse: Cooper drags Fred into danger, torches him, and then uses him to taunt Rachel by forcing him to speak on the phone. The squad arrives, and a tense standoff ends with Cooper wounded as he escapes, stealing a minivan and chasing Rachel and Kyle onto the highway.
A brutal highway pursuit follows, culminating in a violent pile-up caused by a police car that Cooper collides with, and a driver’s fatal crash in his wake. Rachel races to her mother’s old house, pulling Kyle to safety while Cooper corners them outside. A calculated strike shifts the balance: Rachel drives her car into Cooper’s vehicle, flipping it, and she confronts the intruder with a golf club. The struggle becomes personal and visceral as Cooper menaces Kyle; Rachel defends him with a pair of scissors, delivering a devastating blow to the intruder’s strength. In the heat of the moment, she delivers the final, defining action that ends the threat.
As the police arrive to take statements, it becomes clear Fred survived the fire and is on the way to the hospital. The closing moments drift back to the road, where another driver’s transgression nearly causes a new accident, and Kyle privately remarks that his mother made a wise choice by staying focused on protecting him. The film leaves viewers with a tense sense of closure, highlighting the fragility of safety and the lengths a parent will go to in order to keep their child out of harm’s reach.
