- Hefty Smurf
- Sir Lancelot
- Papa Smurf
- Brainy Smurf
- Poet Smurf
- Handy Smurf
- Grouchy Smurf
- Clumsy Smurf
- Jokey Smurf
- Lazy Smurf
- Vanity Smurf
- Harmony Smurf
- Greedy Smurf
- Farmer Smurf (Not seen; heard)
- Painter Smurf (Does not speak)
- Unnamed Smurfs
The episode begins with an ominous sound emanating from the forest. The ground shakes, and fire appears! The forest is aflame, and the animals flee. A giant fire-breathing dragon roams the forest, torching the trees as it passes.
Next, we see the Smurfs gathered round a fire, listening to Poet Smurf wax upon the virtue of the Great Knights of the Round Table. Hefty Smurf is quite impressed with the story, and states that he could have been a knight if it was not for the fact that he is a Smurf. "There's no maiden I couldn't rescue, no dragon I couldn't slay", says Hefty. Smurfette then notices a fire near the bridge over the River Smurf. Brainy goes to tell Papa about the fire.
Hefty organizes a fire brigade, passing buckets from one Smurf to another, to help protect the forest. When they finally finish putting out the fire, Smurfette asks Papa Smurf how the fire got started. Papa Smurf tells Smurfette that he doesn't know and he's thankful that Smurf Village is OK. The Smurfs hear the Smurf Village fire alarm, and the gang runs back to the village.
The village is on fire. Papa Smurf goes to save some of his books. The chemicals in Papa Smurf's lab explode. Eventually, the fire is put under control with the help of the fire engine water pump. Handy is curious as to how the fires were started and Hefty is eager to dispense justice to the guilty. Brainy discovers a set of interesting footprints in the forest. Papa Smurf looks closely at the footprints and lets the Smurfs know that a dragon destroyed their village.
|Meet Sir Hefty, the valiant knight.|
|Hefty meets the dragon.|
|Hefty and Sir Lancealout.|
|Sir Lancealout gets pampered.|
|Hefty gets knighted.|
The Smurfs hold an emergency meeting. Papa Smurf explains that most of his potions and books were destroyed in the fire only two books remain, and because of this, the village has no protection. Papa Smurf declares that a new armament must be created. Poet says they need a knight to protect them. Papa Smurf says he doesn't know of any knights that would protect the Smurfs. Hefty then whispers in Handy's ear.
Later, every Smurf is gathered around Hefty's house. Hefty exits, now dressed as a knight - Sir Hefty. Sir Hefty says that he's going to slay the dragon. The other Smurfs are incredulous. Hefty goes out into the forest in search of the dragon and asks the others not to tell Papa Smurf. Hefty hears the dragon and approaches him with timidity. Hefty decides to find out how brave he really is. The dragon breathes fire on him and Hefty runs away.
Dejected, Hefty mopes along inside the forest. Hefty laments that as a three apples tall Smurf, he can never be a real knight. Then, Hefty sees a knight on a horse galloping by. Hefty is elated to see a real knight. Hefty sets off to meet the knight to get him to protect the Smurfs.
It turns out the knight is being chased by other knights. The knight decides he needs a hideout. The knight is penniless, hungry and thirsty. Just then, Hefty approaches and scares the knight with his presence. Hefty asks if he's a real knight. Sir Lancealout lies and says that he is a real knight. Hefty is impressed and offers the knight a job, protecting the village. Sir Lancealout accepts the job as long as the village is well hidden and there is a lot of food and drinks.
Hefty presents the "knight" to the village, stating that Sir Lancealout will protect the village from the dragon. Papa Smurf seems unimpressed, and the knight is alarmed at the mention of a dragon. Minus Papa Smurf, the rest of the village is smitten with the knight. Brainy shines Sir Lancealout's armor and Handy takes out the dents. The "knight", however seems to keep putting off hunting the dragon, because he is "tired".
Papa Smurf calls a secret meeting. He is concerned that the village could be attacked at any time by the dragon. Papa Smurf goes on to say that he believes the "knight" is not really a knight at all and that he's nothing more than a "common thief and a coward who has no intention of ever fighting the dragon". Papa Smurf has a plan to test the knight's true intentions. He explains that they will build a fake dragon to attack the village and test the knight's bravery and honor. However, the "knight" has been eavesdropping on the meeting and he knows about Papa Smurf's plan.
Sir Lancealout asks Hefty if he wants to be his knight's apprentice. However, a knight's apprentice must always tell the truth, according to Sir Lancealout. Knowing the plan for the fake dragon weighs heavily on Hefty's conscience. Eventually, Hefty confesses about the fake dragon, and the knight tells Hefty he will pass the test with flying colors.
Later, Brainy wakes the sleeping knight crying that the dragon is on the loose! Sir Lancealout agrees to defend the village and take on the dragon - knowing the Smurfs are testing him with a fake. As the fake dragon is steered to the village, it sears the real dragon with its' flames! The real dragon is loose now too! When the "knight" discovers that the fake dragon is real, his yellow nature is revealed. He turns and runs away as fast as he can, dropping his sword and shield. Hefty realizes that his knight is "nothing but a coward".
Hefty decides to defend the village himself. First, he uses the imposter knight's shield to block the dragon's flames and protect Smurfette. The other Smurfs then attack with rocks and anything else handy - including the flames of the fake dragon. Knowing the village is in danger, Hefty leads the dragon away from the village, toward the bridge at the River Smurf. "This is the end of the line for you big fella - time for you to cool off!", says Hefty. Papa Smurf then opens the dam on Hefty's command, and Hefty and the dragon are washed away in the ensuing flood. The Smurfs assume that Hefty's dead. Then Hefty sneezes and the other Smurfs are glad that he's still alive.
Back at the village, Hefty kneels before Papa Smurf and is knighted "Sir Hefty, Knight of the Smurf Table". The Smurfs shout out three cheers of "Hip hip hooray", and Hefty is given a kiss by Smurfette. Hefty responds to the kiss by sneezing again, which closes the lid to his head armor.
- This episode features a coloring mistake. In the scene where Papa kneels to examine the dragon's footprints, his pants are white - not red.
- After Papa Smurf says, "Brainy, you're on.", his mouth is missing for a few seconds.
- When the Smurfs in the fake dragon back away from the real dragon, the real dragon's eyes are white instead of yellow.
- This episode also appeared in a printed book format, called "Hefty And The Dragon".
- Brainy trying to stop Jokey from gifting Lancealout (what he assumes to be) another explosive "surprise", only to destroy the dessert inside, is based on a gag from The Smurfette comic.
- The original gag was also previously used within the same season, namely in the cartoon adaption of said comic.