In a village in a remote valley on the northern border of Xinjiang, China, a lonely Kazakh boy named Arsin nurses fading memories of his family. He finds solace in the company of plants. The arrival of Meiyu, a Han Chinese girl, is like the discovery of a plant he has never seen before, bringing him comfort and a strange sense of wonder. Together, they grow like two distinct species, rooted in a shared corner of the world, imagining the valley as an endless ocean. But one day, Arsin learns that Meiyu will be moving to Shanghai, which is 4,792 kilometres away – a distance he struggles to comprehend. She is headed to a city where the ocean actually exists. Arsin is left alone to grapple with the quiet shifts in their small, fragile world.