The episode starts in a giant cloud where a group of Valkyries are training young Valkyries to be full-fledged warriors. One of them is Artemis who has poor swordsman, shield-wielding, and archery skills. Her teacher gets frustrated with her for not fighting well and says, "Artemis, you need more practice or else you'll never become a full-fledged Valkyrie to protect Oden!"
Meanwhile in the Smurf Village, Papa Smurf tells Joey, Smurfette, Pessimistic Smurf, and Lilac to gather some herbs that he needs for a spell. Pessimistic says, "But if Gargamel's there, we're all doomed! Oh me, oh my!" Papa tells him to not to be so pessimistic and suggests for him to smile; he tries, but then starts to feel pain.
The Smurfs and Pussywillow Pixie leave for the herbs. Lilac is excited, especially because she is with Joey which make him blush, and he thinks, "I don't have enough courage to tell her that I can't be her boyfriend!"
Meanwhile, Artemis is riding on her flying colt named Lilim: she is heading home until she sees the Smurf Forest. Very curious, since she's never allowed to go into the Human world, she fliea down and is amused by the spectacular environment. The flowers, animals, and trees are things that don't exist in the clouds, and then she starts to hear someone singing. She goes to investigate and comes across the Smurfs and a Pixie.
They are collecting herbs when Pessimistic says, "I don't know about you Smurfs, but if Azrael sneaks up on us he'll eat us! Oh me, oh my, oh dear!" Smurfette tells him to not to worry, but he notices the young Valkyrie and says, "I think we're in trouble now - look, a human!" Smurfette and Joey see Artemis.
She tells them to not be afraid and that she won't hurt them. Deciding that she's friendly, Joey and Smurfette approach, as well Lilac and Pessimistic (though he's still not sure if he can trust her).
She introduces herself and Lilim; the Smurfs ask how they've never seen her in the forest before and about her flying colt. She tells them she is a Valkyrie who lives in the clouds with her fellow Valkyries and explains that she is in training to become full-fledged warrior. They decide to help her - since Joey knows how to use a sword, he shows her the basic tactics such as slashing sideways, horizontally, vertically, and a spin attack. She tries the same, but her helmet covers her eyes and she almost crushes the Smurfs and Pixie.
Joey notices that she fights so recklessly because her helmet is too big. Artemis tells them that it was the only helmet they could find for her because, at the time, they were out of stock for young Valkyries. Joey thinks of an idea and decides to escort her to the village to see Papa Smurf. Smurfette agrees, but Pessimistic tells him that it's not a good idea. They disregard him and take Artemis to the village anyways.
Once there, they tell Papa Smurf that they brought herbs and a Valkyrie. Papa Smurf becomes amused and tells them that he has heard about Valkyries, but thought they were just a legend. Not knowing this origin, Smurfette asked for him to explain, so he says, "Valkyries are maiden warriors from the sky. They are Oden's guardians," which amuses them.
Joey informs him about her not fighting very well and believes that if they shrink her helmet to a child's size she show improvement. Papa thinks it is a Smurfy idea, so he reveals his shrinking potion and uses it on her helment. It shrinks down to the right size and she thanks the Smurfs for their help.
Later as a way of showing her appreciation, she helps Joey, Smurfette, Lilac, and Pessimistic gather Smurfberries. Pessimistic says, "I have a bad feeling about this!" Suddenly they hear another voice exclaim, "And this feeling will come true!" All of them (except Artemis) shout, "Gargamel!" He and Azrael start to chase the Smurfs, but Joey manages to drive Azrael away by doing a fast sword attack which intrigues Artemis. He tells her that now's her chance to try her best, so she calls Lilim and jumps on her back.
When Gargamel is cornered, Smurfette and Pessimistic are on a cliff while Artemis and Lilim appear from behind. The noble steed kicks Gargamel, causing him to fall over the edge of the cliff and dive into the water below. While being pulled by waves, he blames the Smurfs for his misfortune by saying, "I hate Smurfs! I hate them, I hate them - I HATE THEM!!"
Later, they thank Artemis and Lilim for saving their lives; she promises to train harder in order to become a full-fledged Valkyrie and says she will never forget them. Joey and Smurfette give her a handshake and watch her fly away. Pessimistic then says, "I don't know, she might forget about us. Oh me, oh my," thus ending the episode.