Anime Reviews writes: "Police officer Ross Sylibus arrives to his new post on the planet Mars and immediately begins to work on his first case. Mars is home to several types of humanized robots that have helped man in making the planet fit for life. Ross follows the tracks of a serial killer called Rene D’anclaude who has been killing robots called Thirds. Thirds are unregistered robots that look and act exactly as humans do. In fact it was D’anclaude who, in murdering one, discovered their existence to the world. Now D’ancluade systematically exposes the Thirds in an attempt to eliminate them all. Ross is aided by a fellow police officer named Naomi Armitage who is a capable officer and an attractive woman. However, Ross soon discovers that Armitage herself is a Third and will not stop until D’ancluade is killed. Ross should aid Armitage in her fight against the murderer. But can he cooperate with her and risk his life to save robots when it was also a robot that, in the past, killed his wife?"