One day in the 1980s, photographer Yoon Tae accidentally discovers a man while taking pictures. He was dressed in shabby clothes, carrying a bag, holding the Taegeukgi in his hand, and was wandering around Seoul , saying unintelligible things. Yun-tae, feeling curious, follows him around. He was a man with the strange nickname 'Mr. Kant'. Mr. Kant visited cathedrals and other places and came into contact with the riot police who stood guard there. Sometimes they say strange things in front of a photographer holding a camera . The photographer who followed him but did not understand him well accidentally learns that he is a missing person from the May 18 Democratization Movement.