在地下的秘密，藏着不为人知的故事与梦想。奔跑吧第四季免费观看

　　A documentary about the underground structures scattered around East Asia and their history. Starting from Busan, the film explores Jeju, Okinawa and many other places of painful history in East Asia. As the recent images are overlaid by past voices, unforgettable historical memories are recalled. The lasting underground structures remain as a scar of history.