The Warners are a typical family, with the usual rifts and arguments. Each year, they leave home on Christmas Day to spend the holidays in a time-share condominium in Colorado. The early-teenaged children, Tim and Julie, are opposed to the idea, preferring to stay home with gifts and friends, but their workaholic father insists that they spend the rare family time together. However, he is inevitably called back to his demanding business each year and is not even there.
On one Christmas, Tim surprises his sister, taking her on an impromptu horseback ride to a mountaintop. There, he shows her an amazing and inspiring display of lights on a distant peak, a scene of mysterious origin that can be viewed from only that one spot precisely at dusk on Christmas Day.
The next year, their father is too busy to make the trip to the condo for Christmas. Even so, the kids can't wait to take their mother on the yuletide horseback ride up the mountain so they can show her the beautiful light show. She, too, is inspired, and when they return home, she tries once more to convince her husband to put his priorities in the right place, to return to church and spend more time with the family. However, by the next holiday, their marriage is over, and so are the rides to the mountain for the Warner family.
Tim blames his mother for the breakup of the family. When he eventually goes away to college, he ends all communication with her. Julie finally takes a Christmas journey of her own, a drive to the West Coast to convince her brother to renew the spirit they found together on that Colorado mountain peak.
He does return home, and at the same time, their father has his own epiphany. The nextChristmas, the parents renew their vows, remarrying on the mountain just as the lights burn their brightest for the reunited family.
A few years later, a tragic turn brings the two siblings even closer, and a special Christmas gift makes certain their bond will never be dissolvednot by distance, hurt, or even death. A final view of the lights on the mountaintop confirms that the love of a family is the strongest tie of all. And a strange but wondrous twist shows Julie Warner the true meaning of those lights they saw on their rides to the Christmas mountain.