When Gargamel meets a giant with an insatiable appetite, he comes up with a plan to use the giant to destroy the Smurfs: tell him that Smurfs make the most delicious soup in the world! Papa Smurf catches wind of the plot, and begins to create a potion that will enable them to turn the giant, nicknamed "Bigmouth," against Gargamel. But when Bigmouth stumbles into the Smurfs village, the potion isn't ready, and the Smurfs must distract the hungry giant, or meet an untimely end inside its belly.

Full-length feature based on the Belgian comics created by Peyo in 1958. The villainous McCreep appropriates the magic flute which was created by the Smurfs. McCreep uses the magic flute, which makes people dance uncontrollably, to steal from others. Court jester Peewit and knight Johan are sent by their King to find the villain and return with the flute. With the help of wizard Homnibus, Peewit and Johan travel to Smurfland where Papa Smurf decides a new flute will be made which will counteract with the original one. But when McCreep and his partner in crime, Flatbroke, plan to invade the King's castle, the Smurfs must come up with a plan to outwit the criminals.