A group of scientists, working in a deep underground lab, clones and hatches a 1,000-year-old dragon, after finding its remains in a cavern in southern England. After the critter goes from one cell to full grown in 3 hours, it goes on a rampage, killing most of the scientists and escaping to the surface. Naturally, bullets don't faze it at all. Our Intrepid Hero helps kill if before it can menace all mankind. Sort of "Alien" meets "Reign of Fire".