Santa Claus does not exist. Or does he? For one doubting boy (voice of Daryl Sabara & Tom Hanks), an astonishing event occurs. Late on Christmas Eve night, he lies in bed hoping to hear the sound of reindeer bells from Santa's sleigh. When to his surprise, a steam engine's roar and whistle can be heard outside his window. The conductor (also voiced of Tom Hanks) invites him on board to take an extraordinary journey to the North Pole with many other pajama-clad children. There, he receives an extraordinary gift only those who still believe in Santa can experience.