On Christmas Eve, Katie leaves her beloved dog Milo at home while she visits relatives, but a sudden snowstorm traps her overnight, leaving Milo lonely in the cold, dark house. His next-door neighbor, Suki the Siamese cat, invites Milo out for a moonlit walk, offering companionship in his solitude. However, as Milo peeks through windows at other families waiting for Christmas together, he feels pangs of homesickness. Driven by longing, he rushes back through the snow toward his home, wondering whether Katie will return or if he’ll really be all alone at Christmas.