On Christmas Eve, the Smurfs prepare for their Christmas party. Hefty Smurf, Gary Basaraba and Handy Smurf cut down a Christmas tree, and by Christmas evening, they all finish and begin to celebrate with carols. Grouchy Smurf, George Lopez refuses to join the party, expressing his hatred toward Christmas, a reaction that catches everyone off guard since he usually puts aside his attitude for the holiday. That night, Papa Smurf, Jack Angel creates a special concoction in hopes of renewing Grouchy's Christmas spirit. The spirit finds its way into Grouchy's mug of smurfberry nog, which he promptly drinks and sinks into unconsciousness. Subsequently, he wakes up to a world that looks like it’s come alive, and he discovers he’s become part of the animation around him.
An angel appears in his house, and it seems to be Smurfette, Melissa Sturm. She explains that she is the Smurf of Christmas Past come to teach him a lesson about appreciating Christmas. She shows him past Christmases he shared with his fellow Smurfs, where each Smurf received their gifts from Papa. Grouchy longs for a hang-glider, but time and again is disappointed by the steady stream of a brand-new Smurf hat as the gift of the moment. After Jokey’s good-natured yet teasing prank, Grouchy loses his temper, sneers at Papa's gift, and begins to despise Christmas.
Next comes the Smurf of Christmas Present, Brainy Smurf, Fred Armisen. He reveals how Grouchy’s reluctance to help with the Christmas preparations forces the others to pitch in and juggle their own tasks, inadvertently delaying their other holiday plans. This pressure ultimately leads Clumsy Smurf, Anton Yelchin, to cause a small accident that sets the Christmas tree ablaze, illustrating the ripple effects of Grouchy’s attitude. The spirit then shows Papa Smurf busy crafting and refining every hat, pouring love and care into each design, and expressing hope that someday Grouchy will see the value in the gifts and in the thought behind them. Grouchy begins to feel guilty for taking Papa's gift for granted.
The Smurf of Christmas Future appears as Hefty Smurf, Gary Basaraba, and warns Grouchy about a bleak outlook if his mood doesn’t change. Hefty paints a troubling vision: if Grouchy stays closed off to the holiday, all the Smurfs may drift into the forest seeking renewal for his spirit, only to be captured by Gargamel, Hank Azaria, and his cat Azrael, Frank Welker. The warning underscores the stakes of his attitude and the importance of community and care.
Grouchy wakes up on Christmas morning, and the world snaps back to its familiar color. The Smurfs rally around him as they decorate the tree together, and he admits that his view of Christmas was wrong. He learns that the holiday isn’t about hatred; it’s about family and belonging, even for someone who stubbornly identifies as “Grouchy.” To mark the turn, Papa Smurf presents his gift first—though it isn’t the hang-glider he once yearned for, it is a hat made with special care just for him. Grouchy accepts it with a warm smile and embraces Papa Smurf, who returns the hug. He tests his new hat by using it as a makeshift hang glider to glide from the top of the tree, ending with a light tumble into the snow. There’s a playful groan as he jokes that Christmas comes only once a year, but the mood is buoyant and forgiving. The Smurfs close the moment by gathering to sing carols and celebrate the holiday together, reaffirming the sense of family that Christmas brings.
