Track of the Moon Beast (1976)

Professor Johnny Longbow Salina a man who really knows his stews introduces Paul Carlson to the practicaljoking Kathy Nolan Paul and Kathy seem to hit it off rather well but during a meteor storm a meteorite fragment strikes Paul burying itself deep in his skull which has the unpleasant sideeffect of causing Paul to mutate into a giant reptilian monster at night and go on murderous rampages It turns out that this sort of thing has happened before when Professor Salina rediscovers ancient Native American paintings detailing a similar event many centuries ago Kathy however still loves Paul and tries to save him