Four hundred years ago, there was an epic battle between the great ninjas and the Youkai, mythical monsters who can summon lightning and grow into giants. The ninjas defeated the Youkai and sealed the Youkai Commander Nuarihyon and his Youkai energies in a cave protected by the "Seal Door." In the present, one of the few remaining Youkai tricks Sasuke and Saizou, descendants of the ancient ninjas, into freeing the Youkai trapped behind the "Seal Door." Now, it is up to Sasuke, Saizou and three other descendants of the great ninjas to come together and become the Kakurangers in order to defeat the Youkai and save the planet!.