Scott Calvin, feeling the effects of age, starts thinking about retiring from his role as Santa Claus. He wants to find someone worthy to take over the job, but before he can make any decisions, a mysterious figure from his past returns with plans to take control of Christmas. This unexpected threat forces Scott to stay in the role longer than he intended.
At the same time, Scott faces challenges at home. Balancing his duties as Santa with being a father becomes harder, especially with his youngest son growing up in the North Pole. His wife, Carol, worries about their family’s future if Scott steps down, making the choice of who should succeed him even more important.
The returning antagonist, a former magical assistant who was banished years ago, aims to replace the magic of Christmas with technology. He spreads doubt among the elves and other magical beings, creating unrest and threatening the very spirit that keeps Christmas alive. The North Pole finds itself in turmoil as faith in Santa begins to fade.
In the end, Scott, with the support of his family and loyal friends, fights to save Christmas and restore hope. His youngest son surprises everyone by showing he is ready to carry on the legacy. The movie concludes with a hopeful new beginning as the next generation prepares to take up the mantle of Santa Claus, ensuring the magic of Christmas lives on.