Nora Walker was a factory worker during World War II, who's husband, Captain Walker, goes missing and is presumed dead. Months later, she gives birth to their son, Tommy. She raises him on her own until eventually meeting Holiday Camp staff member, Frank, and marrying him.
One night, Captain Walker returns to their home, and Frank kills him by hitting him with a lamp. Tommy witnesses the murder, and Frank and Nora frantically tell him "You didn't hear it, you didn't see it. You won't say nothing to no one ever in your life…" The trauma causes Tommy to become deaf, mute and blind.
Nora spends the next several years of Tommy's life searching for a cure, to no avail. One day however, it is discovered that Tommy has an incredible gift for playing pinball. He defeats the pinball champ and becomes wealthy and successful. This causes Nora to indulge in luxuries all the while being haunted with guilt.
One day, while frustrated after a doctor declares Tommy's condition hopeless, she screams at him and demands to know why he can't see her, but seems to see himself in the mirror. She accidentally throws him through the mirror, resulting in Tommy's miracle cure.
Tommy becomes a pseudo religious figure and he and his mother give up their possessions in order to help the needy, and spread their message of anti-materialism, all while Frank schemes to profit from Tommy's decibels. The merchandise being sold by Frank and Ernie at Tommy's Holiday Camp causes the fans to turn on them. They start a riot, killing both Nora and Frank.