A strange type of alien life form was encountered by a team of archaeologists on a desolated planet.
This world, which orbits a binary star system, was once inhabited by a sapient race which built complex systems of underground tombs and passageways. Despite having two suns, the planet's surface temperature is relatively cold, averaging at minus 89 degrees. From the ruins, it has been found that the natives' mythology included a curious devotion to the concept of dualism, which is perhaps related to the twin suns, and they were ruled by twin gods. The scientists also found crystals which emitted a strange energy field, theorized to represent some form of intelligence.
Exactly how that relates to the alien monster is not clear, but said creature attacked two members of the archaeological party, brutally killing one of them, Mitch, and impregnating the other, Sandy. The pregnancy wasn't a natural one, as Sandy had been taking heavy doses of contraceptives. It's more likely that the impregnation was merely a result of the alien laying eggs inside her, which then developed in a parasitic way inside her womb. Said parasites had deep psychological effects on Sandy, causing her to exhibit murderous behavior and even cannibalistic behavior as she killed and consumed the flesh and blood of her teammates. The alien also provoked physiological as well as psychological alterations in her, as shown by the fact that she developed both superhuman strength and the ability to survive on the harsh surface, breathing the toxic atmosphere of the planet. Eventually, Sandy gives birth to twin alien creatures, which kill the remaining team members.
- Inseminoid, a.k.a. Horror Planet (1981)