Howard Langston, portrayed by Arnold Schwarzenegger, is a devoted yet overwhelmed mattress salesman in Minneapolis whose commitment to his career often overshadows his family life. His wife, Liz, and their nine-year-old son, Jamie, though dearly loved, frequently find themselves neglected as Howard chases the demands of his job. To complicate matters, the neighbor, Ted Maltin, a divorcé with lingering feelings for Liz, continually highlights Howard's shortcomings as a husband and father.
As Christmas approaches, Howard becomes determined to reverse his past mistakes by procuring a Turbo-Man action figure, an iconic superhero that has captured Jamie's heart. Despite Liz’s earlier request for the toy, which Howard regretfully overlooked two weeks prior, he embarks on a challenging mission to find one and make his son's wish come true.
His journey takes him from store to store, but disappointment follows him at every turn as the popular toy is sold out everywhere. Along the way, he finds an unexpected rival in Myron Larabee, a postal worker and father who is on a similar quest. Tensions rise as frustration builds, leading Howard to consider unorthodox methods, including acquiring a counterfeit Turbo-Man from a group of Santa Claus impersonators. This disastrous venture results in an all-out brawl in their hideout that attracts unwanted police attention.
Feeling defeated and exhausted, Howard finds a moment of respite at a local diner, where he reaches out to Liz only to find Jamie on the other line. The conversation takes a turn as Jamie reminds his father of his promise to attend the Holiday Wintertainment Parade, causing Howard to lash out in frustration, prompting his son to chastise him for letting them down.
While at the diner, Howard shares his frustrations with Myron, and the two bond over their shared struggles to secure the elusive toy. Myron reflects on his own childhood disappointments, revealing the sorrow of not receiving a Johnny Seven OMA for Christmas, adding depth to their camaraderie. Their heart-to-heart is abruptly interrupted by a radio advertisement for a Turbo-Man contest, igniting a heated argument that leads to a frantic race to the radio station.
Upon reaching the station, they discover that the competition was merely for a gift certificate, sparking a chaotic chase that involves a fake bomb—leading to a series of comical mishaps involving Officer Alexander Hummell, who can hardly believe his eyes when the situation escalates with an actual explosive device.
As Howard returns home, he finds that his car has been stripped bare by thieves, but the evening's holiday spirit briefly lifts his mood as he sees the festive decorations and hears the cheerful laughter of Ted and his family. However, his happiness quickly fades when he spots the Turbo-Man doll that Ted has acquired for his own son, Johnny, reminding him of his ongoing struggle.
In a moment of desperation, Howard contemplates stealing the toy, but ultimately falters when Liz catches him in the act. As the chaos unfolds, his family leaves for the Christmas parade with Ted and Johnny, leaving Howard feeling isolated and frustrated.
Meanwhile, Ted makes an awkward attempt to woo Liz, but she deftly rebuffs him, adding another layer of tension to the evening. As the festivities commence, Howard wrestles with the dual responsibilities of keeping his promise to Jamie and confronting the reality of his failures. The situation escalates into a wild chase involving Hummell and ultimately leads to Howard unwittingly being mistaken for the actor playing Turbo-Man.
Adorning the coveted costume, Howard attempts to give Jamie a unique Turbo-Man action figure, only to find himself pursued by Myron, now disguised as Turbo-Man's notorious nemesis, Dementor. The ensuing chase is thrilling, with jetpacks and high-octane antics leading to a breathtaking showdown.
In the end, as the excitement subsides, Myron faces the law, and Howard steps forward to save Jamie, rediscovering his values along the way. After a heartfelt apology to his family, he realizes the depth of Ted's influence as he finds out that Jamie had already been gifted the Turbo-Man toy by their neighbor.
The evening culminates in a touching moment where Jamie chooses to give Myron the Turbo-Man doll for his own son, showcasing the spirit of the holiday season. As Howard is lifted on the shoulders of an adoring crowd, Myron, Liz, and Jamie share a warm moment of connection amidst the winter festivities.
In a whimsical twist, the post-credits scene reveals Howard back at home, staring at their Christmas tree—its star still unadorned—only to be struck with the realization that he has entirely forgotten to buy a gift for Liz, prompting him to reflect on what truly matters during the holiday season.
