It's November 1952, and America is facing not just a cold winter but a Cold War far more devastating than any history book describes. Four years ago, Russia became impenetrable, leading to wild speculation about the fate of Stalin's Communist regime. Then, in December 1949, the mystery became a nightmare: Hordes of merciless aliens burst across European borders, killing and transforming their victims as they advance. Now the deadly Chimera have crossed the ocean, unleashing lightning strikes on the American mainland. A U.S. Ranger lieutenant, strangely immune to the alien virus attacks, stands as the last, best chance against these extraterrestrial monsters.