X: The Unknown (1956)

Army radiation tests disturb a lurking creature beneath the earth, unleashing chaos on a secluded Scottish village. As the monster, which thrives on energy, wreaks havoc, an American scientist from a local nuclear facility teams up with a British investigator. Together, they delve into the mystery surrounding the victims who suffered bizarre radioactive burns and investigate the strange pattern of radiation incidents that seem to extend in a straight line from the fissure. Their race against time reveals a chilling connection between the experiments and the emerging threat.