Galvanax is the reigning champion of Galaxy Warriors, the most popular intergalactic game show in the universe, where contestants battle to prove who is the mightiest warrior. Galvanax is determined to become invincible by controlling the mythical Ninja Nexus Prism, which contains six supernatural Ninja Power Stars. The only thing standing in his way is a new team of heroic teenage Power Rangers from the city of Summer Cove who possess the Ninja Power Stars. Galvanax sends his warrior contestants down to Earth to steal the Prism where each epic battle against the Rangers is broadcast throughout the universe. Together, the Rangers must master their arsenal of Power Stars, Mega Morph Cycles, and Zords that are made of legendary Ninja Steel in order to stop this evil threat and save the Earth from destruction.