A jockey named Grady is sitting alone in his room after he's found out he's been banned from horse racing for life for fixing races by horse doping. All he ever wanted was to be respected. He curses a reporter who has written of his misdeeds in the paper. He drinks in his depression and thinks of what his life will be now. He then hears a voice. It's his alter-ego.
He argues with his alter-ego, trying to justify his life and his actions, even lying about his crimes. But the alter-ego knows better. Grady is offered the chance to change his life with one final wish. Grady says his greatest wish is to be big. After Grady wakes from his nap he finds his wish has been granted. He's instantly grown taller. He's "big".
Ecstatic, Grady calls his ex-girlfriend over the phone just to prove to the alter-ego that size actually does matter. She angrily wants nothing more to do with him. The conversation gets heated. He screams at her. She rejects him, but Grady remains undaunted. He boasts that he can find more girls that will actually appreciate him because of his newfound height. The alter-ego remains unimpressed, feeling Grady hasn't made good on any of his promises.
Grady however is confused, and asks the alter-ego what he really is, and what his business is all about. The alter-ego tries to explain it to Grady in the most simple way possible. He's "the last gasp". The alter-ego then criticizes Grady for his dumb and "cheap" wish, and gives him better ideas and suggestions for what Grady would've really wanted. The ego implies that Grady could've wished to win the Kentucky Derby, or perform a heroic act, but as it stands, Grady wished to be a "big man". Grady objects, defending his wish.
A telephone call from the racing commission informs Grady that he has been given another chance – he has been reinstated and can jockey again. We hear the alter-ego laughing mockingly. Why? Because now it's too late: unbeknownst to Grady, he has grown even larger, about 10 feet tall — now not only too tall to ride a horse, he barely fits in his own apartment! Grady screams "I'm too big! I can't ride!" Devastated, the now-giant Grady wrecks his room and pleads with the alter-ego, "Please! Please! Please make me small, please! I'll never ask for anything again. Please make me small!"
The alter-ego replies, "You are small, Mr. Grady. You see, every time you won an honest race, that's when you were a giant. But right now, they just don't come any smaller."