在这部海角上的兄妹剧情片中,患有自闭症的妹妹真理子又不见了，这次到了晚上还没回家，哥哥良夫四处寻找。
终于找到了真理子，却发现她和城镇上的男人发生性关系并得到了一万元，将其训斥了一顿。
然而，良夫没有了工作，生计所迫，他抱着罪恶感开始让真理子卖春赚钱，在这种生活中，他渐渐触及了妹妹真实的喜怒哀乐。与此同时，妹妹的内心和身体也开始发生变化...
Two brothers, old brother Yoshio who had a bad one leg, and sister Mariko who had intellectual disability lived in one port town. One day, Mariko was gone from home. A while later, She was protected by the angler. When they coming home, 10,000 yen bills find from pockets of Mariko's pants. He heard that, she said had sex with the angler but, she can not understand what is wrong. After that, Yoshio was fired the company. He was in danger of life, so tried to make a living by prostituting Mariko.
这个妹妹是主动卖身的，也不弱智。岛国卖春片，太他妈反人性了。《海角上的兄妹》不販售奇觀的社會寫實劇。
