During the Japanese occupation, three teenagers from Hsinchu Middle School in Taiwan, Zhou Shaozhen, Zhuang Shigeng, and Lin Qingwen, were successively persecuted by the colonial authorities in the "Imperialization Movement" and forced to leave the campus. They gradually grew up in their struggle for a living. After experiencing the brutal control of the Japanese colonial authorities on the lower classes of Taiwan during the war, their nationalist consciousness gradually awakened, and they took different paths under the influence of the tide of the times. Zhou Shaozhen went deep into the mainland to fight the war, and was displaced and survived. Later, with the help of the Communist Party of China, he joined the Taiwan Volunteer Corps and devoted all his efforts to the national war. Zhuang Shigeng was admitted to the Imperial University, but was forcibly conscripted by the Japanese army and sent to the battlefield, and then escaped from the Japanese army. Lin Qingwen taught Chinese studies in an underground school on the island, preserving the traditional culture of the Chinese nation in his hometown. In 1945, when the Japanese army surrendered, the three reunited in their hometown to build a new Taiwan together. Lin Qingwen chose to go to Xiamen to find new ideas and new ways out, while Zhou Shaozhen and Zhuang Shigeng threw themselves into the wave of the new democratic revolution on the island. But the war came and the three brothers were forced to separate across the sea. After decades of missing each other, they finally reunited in the mainland of their motherland.