Worm 23 years old

An off-screen narrator remembers a time he was five years old, walking to school in a heavy rain, wearing a yellow slicker and cap. He relates to us that a boy he'd never seen before ran up to him and said that it was raining worms. Our lad of five is on the cusp between believing anything he hears and entering the age of reason. He asks for proof. He holds out his hand.