Evil wizard Gargamel is at it again, creating chaos and concocting plans for world domination. After his previous defeat at the hands of the Smurfs, this time he's out for revenge and concocts a devilish plan that brings him to Paris. Gargamel creates a pair of mischievous Smurf-like creatures called the Naughties, Vexy and Hackus, who he hopes will help him harness the magical Smurf-essence. However, Gargamel discovers that only a real Smurf can give him what he needs and his plot takes a wicked turn when he kidnaps Smurfette, the only Smurf who knows a secret spell capable of turning the Naughties into real Smurfs.

Smurfette finds herself in Paris, facing the temptation of the Naughties' mischievous ways. Meanwhile, the Smurfs band together to rescue their dear friend. Papa Smurf takes a bold move and creates a portal to the human world, leading a few select Smurfs to their friends from the past, Patrick and Grace Winslow. The Winslows, joined by their son and Patrick's stepfather, team up with the Smurfs in a race against time. They must navigate the challenges of a bustling Paris and the allure of Gargamel's persuasive offers to Smurfette. As the bonds of family and friendship are tested, they all must work collectively to thwart Gargamel's scheme and save Smurfette before his nefarious plan comes to fruition.