When the body of Army Capt. Elisabeth Campbell is found on a Georgia military base, two investigators, Warrant Officers Paul Brenner and Sara Sunhill, are ordered to solve her murder. What they uncover is anything but clear-cut. Unseemly details emerge about Campbell's life, leading to allegations of a possible military coverup of her death and the involvement of her father, Lt. Gen. Joseph Campbell.

French nuclear tests irradiate an iguana into a giant monster that viciously attacks freighter ships in the Pacific Ocean. A team of experts, including Niko Tatopoulos, conclude that the oversized reptile is the culprit. Before long, the giant lizard is loose in Manhattan as the US military races to destroy the monster before it reproduces and it's spawn takes over the world.