Steve Austin is witness to a UFO at a launch site and, after being dismissed by the ATC and local law enforcement, pursues his own investigation. Meanwhile, a family of explorers from outer space is marooned on Earth after their spacecraft malfunctions. They are unaware that because of their inherent radioactivity, their touch can do great physical harm to human beings, and vice-versa. They come into contact with humans and each time, both alien and human fall deathly ill.