Kojima took an interest in filmmaking when a friend brought a Super 8 camera to school. They began filming movies together, charging other children 50 yen to see them. Kojima tricked his parents into funding a trip to an island off the coast of Japan without telling them he wanted to film there. Instead of filming, he spent his time swimming, and on the last day changed the plot to being about zombies. He did not show the film to his parents.