Robert Day directs this British sci-fi horror. Manning the experimental Y-13 aircraft, intrepid test pilot Dan Prescott (Bill Edwards) flies deeper into space than any man before him. After losing radio contact with mission control, and being bombarded by mysterious cosmic rays, Dan's wrecked craft is recovered hours later back on Earth with the pilot nowhere to be found. However, a spate of gruesome attacks on cattle and then humans, by a bloodthirsty creature, suggests Dan is still alive, if in a somewhat changed form...