"Big friendly giantess, Tasha, is new to the kingdom and wants friends to play with. However, Queen Uniqua simply cannot tolerate giants, especially when she’s trying to take a beauty nap. She summons wizards in training Pablo and Tyrone to get rid of it. They try every spell in the book before finally turning themselves and the Queen into giants, too."
A sandy area is shown with a horse, a tree, and a bucket. Tasha's feet stomp down on the area. The camera zooms out, revealing that the sandy area is actually the sandbox filled with toys. Tasha repeatedly chants, "Boom, boom!" pretending to be a giant or a giantess (a giantess is a female giant). She then looks towards the screen and greets the viewer. She introduces herself as Tasha, the giant, a very large creature. Tasha begins singing "Nobody's Bigger Than a Giant". The backyard transforms into a region filled with trees. Tasha then becomes an actual giant. Then Tasha sings a reprise of the song.
Tasha spots a village far from the forest and begins walking slowly towards it. The camera moves to one of the houses in the small village, where wizards Pablo and Tyrone live. Pablo asks Tyrone if they can try a spell, but Tyrone reminds Pablo that it is difficult to cast spells. The two sing "It's Hard to Be a Wizard". Through song, they explain how they can never get spells right and demonstrate how whenever they try a spell, it comes out wrong.
The two receive a call from the village queen Uniqua through a glass ball. Uniqua tells the boys that she wants them to come to her castle at once. Pablo and Tyrone tell her they will do so. Tyrone tells Pablo that they could use a spell to get to Queen Uniqua's castle from their house. They wave their wands and recite magic words. The spell brings them on top of Queen Uniqua's castle, on a pole. They are hung by the back of their robes.
The camera moves to Queen Uniqua inside the castle. Pablo and Tyrone arrive. Uniqua asks them why they took so long, and they both start talking at once, so she silences them and explains that she is trying to take her royal nap but cannot sleep with the giant causing so much noise, so she orders the wizards to get rid of the giant. They dash out and stop by the castle wall. Pablo starts to worry that they never had to get rid of a giant before; Tyrone replies that he knows, but Queen Uniqua finds them standing in her window, and she yells at them to go. As they rush down the road to the forest, they quickly become winded, as the road is very long. The wizards agree to use a flying spell to get to the giant faster. After waving their wands and reciting the magic words, they start to fly around uncontrollably.
They start flying towards Queen Uniqua's castle and barely escape being smashed into it. Instead, they end up near Uniqua's bedroom, just as she was stretching getting ready for her nap. She notices that they are still at the castle and yells at them to hurry up. They quickly speed away, finally in control, only they run out of flying magic, and they crash down, exhausted. Tyrone offers to take a rest on a circular red item, which he claims to be a rock. The "rock" begins to move, revealing that the rock is actually the shoe of Tasha, the giant. Pablo and Tyrone are petrified and try to run away from Tasha. While they run, they look at Tasha but end up looking up her dress. Tasha is confused, thinking the wizards want to play tag, and yells to the boys that she will get them as she chases after them.
The wizards sing the song "I Know a Spell" using every spell they know. First, they want to transform Tasha into something other than a giant. Pablo suggests turning her into a sheep, so the wizards recite the magic words to a spell in which the giant turns into a sheep. But instead of turning into a sheep, Tasha falls asleep. The wizards are disappointed. Then the wizards try to make the giant disappear. They disappear instead. After turning visible again, Tyrone suggests making the giant go away, but instead, they go to the North Pole. Tyrone tries to get them back again, but instead, they are teleported to the moon. Pablo says that he'll try this time, and they accidentally appear in Queen Uniqua's castle.
Queen Uniqua is angry at the wizards, so they quickly warp themselves away, only to end up landing on the giant's head. The wizards are scared and scream, causing Tasha to giggle as it tickles. The wizards lose their balance on the giant's head and fall into a pond. The wizards are disappointed, and the giant tries to grab the wizards. The wizards swim out of the pond and start running for their lives, but they realize that they won't be getting away with their speed and that they need horses. They try to bring some with their magic, but instead, they turn into horses themselves. The giant starts to chase them, so they run away as horses, neighing. When they almost reach the castle, they run into Queen Uniqua, who claims that she saw everything and orders them to stop horsing around, or she'll get rid of them. They watch her leave back to the castle, and they turn back to wizards.
Meanwhile, the giant is almost at the castle. Tyrone suggests doing the same size spell, even though it is the most difficult trick ever, and they manage to make two giant bubbles (which will make anything the same size as another being if you touch it). The giant sees the bubbles, and she blows them toward the wizards cheerfully. The bubbles pop on the wizards, causing them to become giants.
The wizards are scared of the giant (even though they are all the same size). The giant tags them, and they finally understand that the giant just wants to play tag with them. The wizards worry that Queen Uniqua will be angry, so the wizards make her giant as well. The wizards are happy that they got a spell right for the first time ever, and they play tag while singing "On Top of the World". Pablo's stomach growls, and Tyrone suggests having a snack at his house. The village transforms back into the backyard as the kids sing the end song. They enter Tyrone's house. Tasha opens the previously closed door and shouts, "Yoo-hoo!"