Julie Heart has just turned ten years old and is at the point in her life where she is losing her belief in Santa Claus. It's the week before Christmas, and her magical Dream Pony, Algonquin, is determined she not lose her belief entirely. With his guardian, Mickey Bright, Algonquin sweeps Julie away in the middle of the night. During their first journey, they met the evil Magnifico, and his follower, Billy Green Hat; they returned victorious. On this trip, they travel to the North Pole. Throughout the adventure, the trio encounter a host of characters including gray wolves and polar bears and even an ice breaker. When Julie arrives at the North Pole on the back of Algonquin, she discovers St. Nicholas is on the verge of no longer making trips on Christmas Eve because so many children don't believe in him. Julie finds a way to restore his faith in others so he can continue his Christmas Eve journeys.