The Angry Red Planet

Mission control spots MR-1 approaching Earth orbit, and the team is surprised to see the ship alive. They had assumed the vessel was lost or destroyed in space. With no contact from aboard, technicians guide MR-1 by remote control to a safe Nevada landing.

Only Iris Ryan and Tom O'Bannion survive the mission's four crew. O'Bannion's right arm bears a strange green alien growth, foreshadowing the danger inside. The technicians carefully recover them from MR-1.

During the debrief, Ryan recounts the voyage to Mars and the crew's surface exploration in detail. She describes the events as if they were happening again, guiding the narrative with her medical perspective. She also discusses working toward a cure for O'Bannion's infected arm.

Ryan's narrative covers the long journey from Earth and the preparations for the Mars expedition. The account sets up the dangers they will face and establishes the retrospective storytelling device used for the mission.

On the Martian surface, Dr. Ryan is attacked by a carnivorous plant. Jacobs uses his freeze-ray, Cleo, to kill the plant and protect the crew. The incident proves the planet hosts deadly flora and raises the stakes of exploration.

The crew encounters an enormous creature resembling a rat/bat/spider/crab hybrid in the Martian landscape. Its legs, initially misread as trees, are revealed as part of a dangerous, adaptive predator. Jacobs blinds it with the freeze-ray.

Returning to MR-1, the crew discovers their radio signals are blocked. The ship cannot depart Mars because of a mysterious force field that traps them on the planet.

O'Bannion leads the team to a Martian lake, where a distant city with towering structures is visible across the water. They plan to cross the lake in an inflatable raft to investigate further and seek an exit or answers.

As they cross the lake, a giant amoeba-like creature with a spinning eye attacks and pursues them. Jacobs is captured and pulled inside the creature, and O'Bannion's arm becomes infected by the encounter.

The alien lifeform envelops MR-1, threatening to digest the vessel from the outside. The crew realizes the ship may be consumed unless they can stop the creature.

O'Bannion leads the crew to rewire MR-1 to electrify the outer hull. The electric shock drives the creature away and damages it, allowing the crew to prepare for lift-off. The ship systems are repurposed to enable escape.

The remaining survivors manage to lift MR-1 off the Martian surface as the force field deactivates. Professor Gettell, the ship's designer, dies of a heart attack amid the stress of ascent.

Back on Earth, O'Bannion's infected arm is cured by electric shocks administered by medical staff. The crew’s immediate Martian threat appears resolved as they return to safety.

Mission-control examines MR-1's data recorders and finds a recording of an alien voice. The message states that Mars has observed Earth for thousands of years and criticizes human progress. It hints at a larger, interplanetary dynamic between the two civilizations.

The alien message warns that if future expeditions return to Mars, Earth will be destroyed in retaliation. It accuses humankind of invading Mars and demands cultural progress to match technological growth before sending future visitors.