Eddie Garrick, a dedicated social worker, has always been jaded about the holiday season ever since his childhood, when a mall Santa inadvertently contributed to the separation of his parents. Now as an adult, he finds himself estranged from his wife, Allison Garrick, and grappling with the challenge of forging a bond with their daughter, Charlotte Garrick. While Allison busily wraps up last-minute Christmas shopping, Eddie spends time with Charlotte before heading over to a neighbor's house to care for their pet cat. It’s there that he makes an unusual acquaintance with Nicholas Sinter-Claus, or simply Nick, who claims to be the real Santa Claus.
Surprisingly, Nick seems quite disillusioned with the spirit of Christmas and is paranoid from being followed by three ominous figures. Mistakenly thinking Nick is experiencing a mental break, Eddie brings him along, with Charlotte expressing her curiosity about Nick's enchanting nature. The pair of them becomes captivated by his stories during a chaotic trip to the hospital, where Nick seemingly embodies the elusive magic of the season.
As they attempt to evade Nick's pursuers, the trio embarks on an exhilarating escapade filled with obstacles. Their vehicle breaks down, leading them to hail a taxi, only to find themselves once again under the watchful eyes of Nick's mysterious pursuers. In a moment of audacity, Nick rolls out of the moving taxi and dives into a club crowded with Santas, forcing Eddie and Charlotte to wiggle through the festive crowd.
Their adventures lead them to the eccentric Truckle family, who are fervently passionate about Christmas. With their quirky assistance, they attempt to uncover Nick's whereabouts, but he once again slips away, pushing Eddie and Charlotte to sprint after him.
It becomes evident that Nick is unlike anyone they thought, as he shares that he's been fleeing from dangerous individuals linked to the corrupt Conrad Harf, a congressman holding critical information. The tablet containing sensitive information landed in Nick’s hands, marking him as a target for those wishing to keep their secrets hidden.
Amid growing skepticism, Eddie perceives Nick merely as a burglar and decides to call the authorities, much to Charlotte's dismay. As tensions rise, the audience wonders whether Nick will find the refuge and solace that he so desperately requires.
When the police station’s doors open, Nick is unexpectedly seized by Conrad's henchmen disguised as law enforcement. Meanwhile, Eddie recalls that Nick had entrusted him with the tablet, and upon reviewing its contents, he reveals the astounding reality of Nick’s story.
Armed with this newfound revelation, Eddie and Charlotte set off on a brave rescue mission to find their missing friend. Their quest leads them to Conrad's lavish Christmas party at City Hall, where Nick is being held against his will. Just as Eddie attempts to save him, they are ambushed by Conrad’s thugs.
Unfazed, Eddie utilizes his trusty reindeer caller, summoning the magical creatures that had always accompanied Nick. The reindeer charge in, swiftly taking down the henchmen, leading to Conrad and his crew being handcuffed. With justice restored, Nick shows a surprising act of charity, gifting a long-desired Action Arthur action figure to Conrad, his erstwhile adversary.
As Nick departs with his reindeer companions, Eddie and Charlotte return home, where Allison is awestruck by their whimsical tales of Christmas wonder. Just as she begins to dismiss their adventures, Nick makes a splendid entrance, presenting a delightful surprise – a playful puppy named Bulldozer, a promise he had made to Eddie. This heartfelt gesture sparks a renewed connection between Eddie and Allison, prompting them to invite the Truckle family over for the holidays. As Nick takes off into the starry night, having fulfilled his festive duty, the stage is set for an enchanting season brimming with love, joy, and an abundance of holiday cheer.
