The film opens in 35,000 B.C., in what will become North Texas. Two cavemen hunters encounter a large extraterrestrial life form in a cave, which kills one and infects the other with a black oil-like substance. In 1998, in the same area, a boy falls into a hole and is also infected by a black substance which seeps from the ground. Firefighters who enter the hole to rescue him do not come out. A team of men wearing hazmat suits arrive and extract...