So what happens when a little boy named Tommy Walker witnesses his father, who just came home from being M.I.A. in WWI for almost 6 years, brutally murdering Mrs. Walker's boyfriend? He mentally shuts down, making himself become deaf, mute, and blind for the majority of his life, from his childhood to his young adulthood. So this is what the whole concept of Tommy is about. And THIS is the song in which the murder happens.