In 1990, space travel is well-established, with humanity having already set foot on the Moon two decades earlier. Laura James [Judi Meredith] [Judi Meredith] monitors strange signals from outer space, and her supervisor, Dr. Farraday [Basil Rathbone], works to translate them. The breakthrough comes when they realize the signals originate from an alien race that plans to send an ambassador to Earth. Not long after, Laura receives a video log that reveals the aliens’ starship has crash-landed on Mars, changing the mission from observation to rescue.
The International Institute of Space Technology quickly axes a plan: a rescue mission aboard the ship Oceano, carrying Laura and two astronauts, Anders Brockman [Robert Boon] and Paul Grant [Dennis Hopper]. The crew pushes through a sunburst and endures some damage, but their determination carries them to Mars where they discover the downed alien craft. Anders and Paul investigate and find only one alien survivor, while Dr. Farraday deduces that the rest of the crew might still be alive somewhere. To locate the alien rescue ship, they decide that an observation satellite is essential. Laura’s fiancé Allan Brenner [John Saxon] and fellow astronaut Tony Barrata [Don Eitner] volunteer for the dangerous task. They blast off aboard the Meteor and head toward Phobos, Mars’s closer moon, to deploy the satellite. On Phobos, the pair unearth an alien spaceship and manage to bring back an unconscious yet living female alien for study aboard Oceano.
With limited space for two passengers, a coin toss determines who stays behind: Tony Barrata remains on Phobos while Allan Brenner returns to join Laura, Paul, and Anders. The alien awakens on board and her initial calm gives way to a chilling response: she smiles at the men but not at Laura, refuses food, and resists a blood sample from Anders. That night, while Paul keeps a watchful guard, the alien exerts a hypnotic influence and kills him, draining his blood. The crew makes a dangerous choice to sustain her by feeding her plasma, hoping to keep her contained. When the plasma runs dry, the alien claims Anders next, leaving Laura and Allan as the sole surviving humans aboard Oceano.
The tension escalates as the alien launches another attack on Allan, but Laura intervenes. A fierce struggle ensues in which Laura manages to wound her, yet the alien’s screams reveal a terrifying vulnerability. The creature collapses and bleeds out, dying in the ship’s dim lights. In a startling discovery, Laura and Allan uncover alien eggs hidden aboard Oceano, hinting at a larger, looming plan. Allan proposes a troubling hypothesis: the alien was royalty—likely a queen—and Earth has become her target for breeding. Before they can act on this revelation, Earth authorities decide to study the eggs rather than destroy them, raising questions about humanity’s next steps in the face of an potential extraterrestrial breeding program.
