张登平

An extraordinary light incident ten years ago led to the mysterious disappearance of Zhang Peng's friend. Ten years later, a film crew director approached Zhang Peng with the idea of returning to Xiangshan, the site of the incident—a remote small town built during the Sino-Soviet confrontation in the 1960s, known as the "Third Front"—to shoot a film seeking the truth.

Wu Zonghua, who suffers from Alzheimer's disease, has always been at odds with his family, especially with his son Wu Yong. Just before the end of his life, Wu Zonghua insisted on going back to Jialing County, where he had worked in his youth, to visit his old comrades. Because his father is unable to take care of himself, his son Wu Yong accompanies Wu Zonghua on this journey.