Doctor Who and the Silurians(1970)

Doctor Who and the Silurians is a science fiction serial that follows the Doctor as he investigates power failures and a death at an underground research facility. He uncovers a shocking truth: a colony of intelligent prehistoric reptiles, the Silurians, has awakened from hibernation. Believing humanity stole their world, the Silurians plan to exterminate mankind using a devastating plague. The Doctor must navigate the tensions between the research centre staff and the alien species while racing to prevent genocide. The serial explores themes of territorial conflict and the possibility of coexistence between two intelligent races fighting for survival on the same planet.