During a underground scientific expedition, scientists discover a kaiju digging underground. While the scientists are being attacked by the kaiju, some researchers at the Kaiju Research Center research the kaiju. When they discovered his name is Tsuagon, they went on expedition to study him. Unnoticed by them, Tsuagon was already in downtown New York City. He destroyed everything in his path. Soon, once he saw a young girl named Ariana. When he quickly fell in love with her, he saw the beauty in humans, so he decided to protect the human race from other kaiju threats.