The film is set against the backdrop of the Great Victory of Pingxingguan, and tells the story of Zheng Zhong, a cryptographer who was surrounded and hunted down by the Japanese for his crucial role in turning the tide of war.

Zhang Xiaohong, a struggling coach, leads Wang Cai and a group of Wa ethnic boys from Yunnan through various hardships. Together, they demonstrate that there are no class distinctions in tennis. In their pursuit of the national championship, they leave their mountainous village and learn to overcome challenges along the way.