Synopsis

The undersea pedestrian tunnel, a straight and unremarkable 780 meters beneath the Kanmon Straits in southwestern Japan, consistently draws visitors. While many utilize it for practical passage between Fukuoka and Yamaguchi prefectures, others seek a more personal connection to the structure. The clientele is varied: a young woman revisiting cherished memories with her partner, a man conducting clandestine marathon training, a woman maintaining a weekly ritual with lifelong friends regardless of