It's Christmas Eve on Sesame Street, and everyone is joining in the excitement - until a question from Oscar throws Big Bird into a tailspin. How does a guy like Santa Claus, who's built like a dump truck, come down all those skinny little chimneys? Oscar asks. Suddenly Big Bird is worried that if he can't answer the question, there won't be any presents on Christmas! With the help of all his Sesame Street friends, Big Bird attempts to solve the mystery. But in the process, he discovers that the true miracle of Christmas isn't the presents under the tree, but the spirit of loving and sharing.