When virtually all of the residents of Piedmont, New Mexico, are found dead after the return to Earth of a space satellite, the head of the US Air Force’s Project Scoop declares an emergency. A group of eminent scientists led by Dr. Jeremy Stone scramble to a secure laboratory and try to first isolate the life form while determining why two people from Piedmont – an old alcoholic and a six-month-old baby – survived. The scientists methodically study the alien life form unaware that it has already mutated and presents a far greater danger in the lab, which is equipped with a nuclear self-destruct device designed to prevent the escape of dangerous biological agents..

Senator Walter Chalmers is aiming to take down mob boss Pete Ross with the help of testimony from the criminal’s hothead brother Johnny, who is in protective custody in San Francisco under the watch of police lieutenant Frank Bullitt. When a pair of mob hitmen enter the scene, Bullitt follows their trail through a maze of complications and double-crosses. This thriller includes one of the most famous car chases ever filmed.