One person out of every thousand is born with autism. It follows that China has over one million autism patients. David is one of them: he looks absent-minded, repeats other people's words, swims with amazing ease, keeps everything at home in exact order… and maybe he is not totally aware of his mother's death some years ago. Working in an aquarium, Sam Wong takes tender care of this twenty-two-year-old son of his. With the generous help of the neighbors, the two live happily together. Yet, the father understands very well that in the end, he will have to depart from the world, leaving his son alone – and that day will come sooner than everyone is ready to believe. This film is an ode to a father who is determined to find shelter for his son before it is too late. In the process, the boy achieves a measure of independence necessary for both to let go.