On Christmas Eve, the Muppets go to the post office in New York City to deliver each of their letters to Santa Claus (Richard Griffiths). When they head back to their apartment, Gonzo discovers that three letters wound up in his coat from a mishap there. One of those letters he recognizes as being written by his friend, a neighbor girl named Claire (Madison Pettis). On Gonzo's insistence, the principal Muppets decide to go to the North Pole and deliver them personally.