The three men all have the character "yi" in their names, and they also sworn brothers and became brothers, but they ended up on different paths in life. The three fell in love with a girl named Ye Yushan at the same time. Tang Ziyi accidentally saved Ye Yushan's life. But later, Tang Ziyi had frequent incidents during the war, and he hadn’t come back after going out for many years. There was an extra girl, Liu Suya, by his side. Liu Suya was also infatuated with Tang Ziyi, and finally the two became husband and wife. Suo Zhiyi has been guarding Ye Yushan's side for many years. When Ye Yushan knew that Tang Ziyi had married, she also fell in love with Suo Zhiyi who devoted herself wholeheartedly to her. Both of them joined the Revolutionary Army and worked hard for the Anti-Japanese War. And make a partner. Gu Renyi was timid and fearful. When the Japanese army invaded China, the three originally fought against Japan together, but in the end Gu Renyi became a traitor because he could not stand the temptation. The three brothers became hostile since then. Gu Renyi had a son and was killed by the two A sworn brother was shot to death, and for the sake of brotherhood, the two adopted Gu Renyi's son