Chi is a lousy real estate agent who muddles through life. Growing up, his mother has always told him to lead a simple life, until he reunites with his primary school P.E. teacher, Mr Wong. Mr Wong, who’s been increasingly ill, wants to keep his promise to his late wife to finish a 10k race; At the same time, his student, an overweight student called Tin Sum aims to finish her first ever 5k race just so she can run with her idol. As Mr Wong and Tin Sum fight for their goals, Chi, discouraged, stands at a crossroad and roams aimlessly in life. Until one day, memories from 20 years ago light up Chi’s world. For once in his life, Chi swears to cheer himself on.