Tensions are escalating across the United States as the recently deceased rise from their graves, transforming into mindless, flesh-hungry ghouls. Amidst this chaos, Fran (Gaylen Ross), a dedicated employee of WGON-TV and Radio, discovers that her program director, Givens, is misleading the public with outdated information about rescue stations that are now overrun by the undead. Meanwhile, her boyfriend Stephen (David Emge), a traffic helicopter pilot, arrives with urgent news: they must escape immediately to survive. He plans to take the station's helicopter and instructs Fran to meet him on the roof by 9 PM.
At the same time, a SWAT team in Philadelphia prepares to storm a tenement building occupied by impoverished African-American and Hispanic refugees who are reluctant to abandon their homes and the bodies of the dead, whether deceased or reanimated, which they are hiding in the basement. During an intense gunfight on the roof with armed criminals, Roger ([Scott H. Reiniger]) becomes unnerved by the bloodlust displayed by certain members of his team, especially when one, named Wooley, loses control and opens fire indiscriminately. A tall man in a gas mask intervenes and shoots Wooley, bringing a moment of respite to the chaos.
Seeking refuge, Roger retreats to the basement of the building, where he encounters the masked figure, who identifies himself as Peter (Ken Foree). As they smoke and share a brief moment of camaraderie, they acknowledge the escalating zombie threat. Roger mentions his friend Stephen's helicopter plan and suggests Peter join them in their escape. Just then, an elderly Hispanic priest appears, missing a leg and maneuvering with a crutch, having administered last rites to the dead. He grants the SWAT team the authority to act as they see fit regarding the corpses.
Roger and Peter make a desperate bid as they clear the zombies from the basement, grappling with the grim weight of their situation. Meanwhile, Stephen and Fran arrive at an abandoned police station pier on the Delaware River to refuel the helicopter and await Roger. Their arrival is met with hostility from four rogue policemen, but Roger and Peter come to their aid, diffusing the situation. Although surprised by Peter's presence, Stephen and Fran agree to take him along.
The following morning, after landing at a deserted airport depot to refuel, they are ambushed by zombies, forcing Stephen to confront his inadequacies while he attempts to protect Fran—who is pregnant—only for Roger to save the day instead. Subsequently, they spot a deserted shopping mall and decide to investigate its potential for providing shelter. After a perilous landing, they break in through a skylight and are met with hordes of wandering zombies throughout the building, which seems to be eerily deserted yet filled with the remnants of their former lives.
The group theorizes that the undead may have been instinctually drawn to the mall—a place that held meaning for them during their lives. With a gun shop at their disposal for acquiring firearms and ammunition, they start gathering essential supplies, hopeful that they could sustain themselves for a while. The trio begin making the mall their unlikely home, utilizing Peter, Roger, and Stephen's skills to build a secure haven, while Fran reluctantly agrees to their plans, driven by her sense of duty as an expecting mother.
As days turn into weeks, they confront the reality of their existence. Roger sustains a fatal bite from a zombie while trying to make a reckless retrieval of items. With clear signs of impending death, a heartbreaking decision is made to let nature take its course, despite Fran’s wishes to seek medical help. Roger’s eventual transformation into a zombie forces Peter to carry out his promise and end Roger's life for good.
As everyone struggles with the emotional toll of survival, Fran's pregnancy progresses while their spirits wane. Their sanctuary slowly transforms into a psychological prison as they grapple with mounting isolation, leading to discord among them. A confrontation with a gang of ruthless survivalists leads to dire consequences, including Stephen being wounded and ultimately succumbing to a zombie attack.
In a desperate bid for freedom, Peter and Fran navigate the chaos as the horde of undead descends upon the mall, culminating in a gripping escape attempt via helicopter as they fight for their lives against overwhelming odds. With dwindling resources and uncertainty looming over their future, Peter and Fran take flight into an unknown world, grasping for survival amidst the shadows of a crumbling society.
