Twelve years on, an unexpected aftershock occurs. During a primary school reunion, Xiao Li reconnects with Song Qian, a girl who once harbored a secret crush on him. Afterward, by the riverbank with the camera his father left him, Xiao Li captures an image that seems to be an old childhood companion. Ghosts of the past resurface, stirring up the long-buried secret of his father's disappearance and memories of a tragic game of hide-and-seek by the river. Amidst the flowing waters, Xiao Li confronts the revisiting specters of memory and the crossroads of his current life.