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Chapter 1: Employee of the Year
SpongeBob wins the "Employee of the Month" award once again, so Mr. Krabs decides to name him the "Employee of the Year". He then receives a mysterious mail package containing two free tickets to "Neptune's Pacific Paradise", and later gives them to SpongeBob for winning the "Employee of the Year" award.
They get out of Rock Bottom, but SpongeBob and Patrick do some annoying things on the bus, so the bus driver says that the bus ran out of gas. SpongeBob and Patrick get tricked, so they get left behind and they have to find a new way to get to Neptune's Paradise. The goal is to get on Sandy’s rocket.
The oxygen fuel tank in Sandy's rocket runs out of oxygen (thanks to Patrick), and they get stuck in Bottoms Up. The goal is to get the oxygen tanks filled so that SpongeBob and Patrick can get to Neptune's Paradise. But the real question is "where are the oxygen tanks?"
In the ending sequence, SpongeBob and friends get to Neptune's Paradise, but an employee tells them that the park is closed to make way for a private party. SpongeBob and Patrick cry. He says it's "SpringBoob SquirePin"'s party, and Sandy tells him that he made an error in pronunciation. SpongeBob and Patrick are overjoyed, and several characters that they met throughout the game jump out and say: "Surprise!". They all ride the rides and have a lot of fun. The end shows them all leaving Neptune's Paradise, except Patrick, whom is still on a ride.
Somewhere in each chapter, a mysterious character known as "The familiar man" is encountered. When SpongeBob notes that he has seen him before, the man denies ever having met him. At the end of the game, it is revealed that they are thousands of identical brothers, and that SpongeBob met a different one each time.
The outfit that Patrick wears throughout most of the game, (consisting of a green baseball cap, a lavender shirt, his usual green swimtrunks with purple flowers, and a camera,) is seen on him in the beginning of "Neptune's Spatula."
If one clicks on the Operation Krabby Patty poster in the television station, SpongeBob breaks the fourth wall by saying, "Operation Krabby Patty, that was my very first game. Good times, good times."
But this isn't canon because "Legend of the Lost Spatula" was ACTUALLY the first game SpongeBob was in.
In Chapter Two, there is a man named Jojo fixing an antenna who asks SpongeBob for a soda and SpongeBob gets him a Diet Caffeine Free Coral Cola with a Lemon Twist; this is a reference to the episode "No Weenies Allowed."
When pointing the cursor over the giant candle in the room with the Slot machine in chapter two, the game will say, "Look at Giant Freakin' Candle."
SpongeBob notices a calendar from 1969 at Sardine's Sundries and asks "Who are the Doobie Brothers?"
When Mr. Krabs opens the envelope containing tickets to Neptune's Paradise, the name "Nickelodeon" can be identified on the blurred-out stamp. Also, in the PC version of Battle for Bikini Bottom it is featured as a demo.
SpongeBob has a pinup of Sandy in his locker at The Krusty Krab. If you click on it, he says, "Sandy Cheeks, looking at her makes me smile," hinting at a possible romantic connection between the two.
If one looks at Sandy's Treedome while the rocket is blasting off, there are two trees.
After talking to the Information Lady in Rock Bottom, she says, "You can check out any time you like - but you can never leave." This is most likely a reference to the song "Hotel California" by the Eagles.