An ageing fishing boat, Dai-go Fukuryu Maru ("Lucky Dragon No. 5") sets out from the port of Yaizu in Shizuoka Prefecture. It travels around the Pacific line fishing. While the ship is near Bikini Atoll, the ship's navigator sees a flash. All the crew come up to watch. They realize it is an atomic explosion, but take time to clear their fishing gear. A short time later, grey ash starts to fall on the ship. When the ship returns to port the sailors have been burned brown. They unload the fish, which are then transported away. They visit the local doctor and then go to Tokyo for an examination. It turns out they are all highly radioactive. Their symptoms become worse, and the contaminated fish causes a panic.

By going to the Philippines, Imamura comes to meet people living in an extreme poverty. He discovers very quickly that some communities are under the control of cruel & armed pirates. Imamura will come to meet those men in order to understand their position.

Michio Yamada, a recent school graduate, is sent to Tokyo to work as a fruit-packer in a department store as part of a government programme. He takes a gun from a house on an American base and uses it to kill several people. The scene changes to Yamada's childhood. Yamada is born the child of a reprobate and a weak-willed woman. As a boy Yamada, experiences poverty and the rape of his sister at first hand.