The narrator explains that sometimes every day was a holiday for SpongeBob, even if he had to make one up. SpongeBob then wakes up with a Viking costume on, and exclaims "Hey everybody! It's Leif Ericson Day! Hinga Dinga Durgen!" He then goes outside to play with his friends, but finds notes at the houses of Patrick, Sandy and Squidward notifying that they cannot play. Squidward's note even says he does not want to play with SpongeBob at all, rather than Patrick and Sandy who were busy. SpongeBob decides to make a new buddy, and after several failed attempts, creates a humanoid, happy bubble named Bubble Buddy. The two go to the Krusty Krab, where SpongeBob orders everything on the menu for Bubble Buddy. However, SpongeBob explains several specifications that Squidward has to adhere to in order to satisfy Bubble Buddy's alleged preferences (lactose intolerant, etc.), making him remake the patties several times. After the meal, Bubble Buddy pays in "bubble-money" (which pops, and is feign money) and leaves a tip of "bubble coins" which also pops, making Squidward and Mr. Krabs mad.
SpongeBob and Bubble Buddy then go to the Goo Lagoon, where they continue to cause trouble, even resulting in the demise of one fish. Eventually, the Bikini Bottomites become fed up with Bubble Buddy and begin to riot, even tipping over the lifeguard tower. Squidward steps in and blames SpongeBob and the bubble he has created, causing the mob to direct their efforts towards popping Bubble Buddy. They surround SpongeBob and Bubble Buddy, brandishing sewing needles and screaming repeatedly to pop the bubble. SpongeBob tries to inform the crowd that Bubble Buddy is uncomfortable around their pointy needles, but they tell him that they are done with Bubble Buddy. SpongeBob tries to escape by inflating Bubble Buddy, but he flies weakly back into the crowd's grasp. SpongeBob says Bubble Buddy is his special friend and tries to ask if they ever had a special friend. Although some do reveal that they do have a special friend, it is not enough to change their mind. They then throw SpongeBob out of the way. Squidward begins to stab Bubble Buddy, but he suddenly comes to life and catches the needle before it reaches him, much to the shock of Squidward and the other crowd members. Bubble Buddy then tells SpongeBob that "things are getting a little weird around here," and leaves in a bubble taxi, flipping into the sky, wishing SpongeBob a Happy Leif Erikson Day. Everyone appears to be OK with Bubble Buddy leaving Bikini Bottom except Squidward who is still shocked at what happened. The rest of the crowd then leaves to go on with their regular lives and SpongeBob happily cries that people grow up so fast before leaving in a flurry of bubbles. All but one of them pop, and Squidward greets it.
During all of the scenes when SpongeBob is at Goo Lagoon, if you closely, you will notice that SpongeBob's socks are just colored white instead of his usual white socks with red and blue lines on them.
Bubble Buddy did not appear again for 11 years in an episode until "Bubble Buddy Returns" in 2011.
It is unknown why Scooter still appears after he died in this episode.
The line "He delivered a plague onto our houses" references a scene in Shakespeare's play Romeo and Juliet where Mercutio says "I am hurt, a plague on both your houses!"
When SpongeBob was looking at the menu for the Krusty Krab, one of the food mentioned was the "Quarter Ouncer Double Pounder." This may be a parody of McDonalds' burger the Double Quarter Pounder.
The captions cut off too early at several points in the episode, and sometimes only stay on for a split-second before disappearing; the same goes for its sister episode, "Big Pink Loser."
In this episode, Chuck Klein's name was spelled wrong in the opening credits with the I and E reversed (Chuck Klien).
During the scene with the menu, the prices are gone.
When Bubble Buddy was in the bathroom, hundreds of fish were in line waiting. But when SpongeBob and Bubble Buddy leave, only about ten fish are in line.
When Francis says that SpongeBob kept them waiting for a bubble, there was a black whale in the line. But when Larry says that he called him fat, the whale was next to Larry.
Evelyn has sunglasses that repeatedly disappear and reappear throughout the episode.
When Squidward gave Bubble Buddy a Krabby Patty, there was no cheese inside it. When SpongeBob was about to look in the Krabby Patty, there was cheese inside it.
In Indonesia, Sandy's note is narrated by SpongeBob, instead Sandy herself.
After Squidward is done with every way "Bubble Buddy" prefers his patties, even though Squidward says that the bun on the Krabby Patties have no crust, you can clearly see there is crust on the buns.
In this episode, Mr. Krabs was seen with white chest hair, but in other episodes, he has black chest hair and sometimes no chest hair.