Watch Reign in Darkness for Free: How to Stream the Movie Online at 123Movies. . Biologist Michael Dorn is infected with a virus designed as a cure for HIV, but which turns its victims into vampires. Now a threat to the very organisation for which he worked, Michael is on the run and must decide the fate of the world. His options: destroy all knowledge of the virus, or succumb to the power and delights of this dark and evil way of being.