The story takes place in the year 2025. However, peace is short-lived as the planet-conquering Troobian Empire turns its destructive attention to Earth. When the Earth's first line of defense, the S.P.D. A-Squad mysteriously vanishes without a trace, the protection of the planet falls to their replacements: the B-Squad Rangers, under the guidance of their dog-like alien commander, Anubis "Doggie" Cruger.