Yuta, a young master at the Tsukiji Fish Market, accidentally drops his meal of mixed seafood into the Sumida River. Some time afterwards a gigantic mutated squid monster arises from the depths and begins to wreak havoc upon an awe-stricken Tokyo. As a last ditch effort, the government forms the "Seafood Monster Attack Team (SMAT)" and an all-new plan of attack is immediately put into action.
