Sirius, immortal Lord of the Dog Star and infamous for his fiery temper, is outraged when he is falsely accused of murder and banished to Earth. There, he must live -- and die -- in the body of a dog unless he can retrieve a mysterious celestial weapon and thereby clear his name.On Earth, Sirius is adopted by Kathleen, who has no idea that her beloved dog is anything more than an abandoned stray. With only dim memories of the star-world from which he has fallen, Sirius embarks on his mission. But his quest seems hopeless...until at last Sol, Moon, and Earth themselves come to his aid.