In a quiet English village, an unprecedented catastrophe has occurred, leaving human bodies scattered across the streets as if struck by a sudden and widespread disaster. A small, resilient group of survivors congregates in the local hotel bar, trying to make sense of the chaos around them. Leading this group is Jeff Nolan, an American jet test pilot, who quickly realizes that the situation is dire and evolving rapidly. It appears that most of the Earth's population has been wiped out by a mysterious gas attack, which has turned the city into a contaminated wasteland.
As the survivors gather, they witness unsettling sights, including figures clad in space suits roaming the desolate streets. One of the survivors, Vanda Godsell as Violet Courtland, initially thinks these space-suited figures have come to rescue them, but her hopes are dashed when these beings turn dark and deadly, approaching her with lethal intent and killing her with their touch. These intruders are seemingly invincible, adorned in suits that make them bulletproof, and they stalk the area as relentless killers, adding an overwhelming sense of dread to the survivors’ plight.
Among the new arrivals are the heavily pregnant Lorna Brenard and her moody husband, Mel. They arrive by car, having recently broken into a fallout shelter to escape the chaos of the outside world. Their presence in the story introduces a new layer of vulnerability, especially with Lorna on the brink of giving birth. The group seeks refuge at a local Territorial Army drill hall, where they attempt to arm themselves for the fight against these deadly invaders. Tension is high as they prepare to defend their lives and attempt to understand the nature of their enemies.
The situation takes a darker turn when Violet Courtland reanimates as a zombie, her eyes turning white in a haunting transformation. This shocking event emphasizes the depth of the horror, and Quinn Taggart [Dennis Price] instinctively shoots and kills her to prevent further chaos. Afterward, Quinn manages to incapacitate Jeff Nolan and then departs with Peggy Hatton, heading north in a sportscar. Peggy tries to escape when Quinn stops for petrol, but her attempt is thwarted when she insists on having a coat. She eventually finds herself trapped in a house, pursued by zombies and foes in suits, and hides in a wardrobe to avoid capture. When the danger subsides, she escapes outside, only to be rescued by Jeff, who has been searching for her.
In a tense turn, Jeff runs down a strange creature in his Land Rover—initially believed to be an alien, but revealed to be a robot that explodes upon impact. The survivors regroup back at the drill hall, where Lorna Brenard is close to giving birth—a poignant moment amidst the chaos. Meanwhile, Edgar Otis [Thorley Walters], struggles with the reality of the invasion, drowning his fears in alcohol as he grapples with the terrifying new world around him.
Jeff and Mel Brenard work together to locate the source of the alien control signals using shortwave radios and triangulation techniques. Their efforts lead them to a transmitter tower, which they plan to destroy, hoping to disable the invading robots. As they approach their target, they are met with an onslaught of hostile robots, including Quinn—now a zombie—and two more robotic beings. One of the robots approaches Peggy, adding to the tension, but as the tower is destroyed, all the robots suddenly collapse—signaling a temporary victory.
The film reaches a critical climax when Otis shoots Quinn, who had become a zombie, saving Peggy, Lorna, and her newborn daughter. With the immediate threat neutralized, the survivors seize a Pan Am Boeing 707, aiming to escape the devastated region. Their goal is clear: to fly south and seek out other survivors, in hopes of rebuilding and understanding the true scope of the invasion that has brought humanity to the brink of extinction.
This story is a vivid depiction of survival against overwhelming odds, combining elements of science fiction, horror, and human resilience in a world turned upside down by an alien invasion with deadly, relentless robotic foes. It highlights themes of hope, fear, and the unbreakable will to endure amidst catastrophe.
