Xu Xiaotong, a handsome man who seems calm and dull to others, but only he knows that he was once a cheerful boy. Because of an accident, his beautiful childhood was broken and the lively and cheerful boy turned into the poker face he is now. He disguises himself and smiles politely, but he doesn't laugh from the bottom of his heart. Until he met her, Xiao Tong, his dull life began to change.