"Specimen: Unknown" is an episode of the original The Outer Limits television show. It first aired on 24 February 1964, during the first season.

The crew of the Adonis research space station discovers an unusual object attached to the station wall and brings it inside to study it.

Lt. Howard (Dabney Coleman), a member of a team of astronaut-researchers, finds a strange mushroom-shaped organism clinging to the outside of their space station. Exposed to light and air inside, it develops into a beautiful flower, but has a deadly scent and an aggressive growth habit. Upon Howard's surprising discovery of the organism's rapid metamorphosis, while attempting to further study its cellular make-up under the microscope following the spewing of tiny spores, the flower emits a noxious gas that temporarily incapacitates him, after which he dies. When the other astronauts attempt to return to Earth for help, they bring the invasive new species along with them. Learning of the potential danger to life, their superiors on Earth order the ship's crew to remain in orbit until a method can be found to eliminate the threat of world-encompassing genocide. As the spacecraft runs out of fuel, the half-dead crew is forced to crash-land near the rocket base, where a team of scientists and military personnel immediately descends upon and surrounds the crash site in an attempt to contain the spread of the organisms, which, by now, have fully engulfed the interior of the ship and begun to sow upon the surrounding countryside. Continuing to spew their spores and spray the air with their deadly gas, the creatures scatter themselves across the earth, while storm clouds form overhead, with everyone fearing the worst - What will become of the human race when the rain begins to fall? As all hope for survival is about to fade, the sky opens up and drenches the land with life-giving rain. But, ironically, the flowers begin to wilt, and they eventually succumb to the effects of mother nature.

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