[The episode begins with Patchy rowing his boat next to Bikini Atoll.]
Patchy: Stroke! Stroke! Stroke! [turns to the screen and laughs as his hat spins] Hey, kiddies! It's your old pal, Patchy, floating somewhere over Bikini Bottom. I sailed down here to witness something that only happens every 100 years. Why, me and my trusted parrot, Potty, wouldn't miss it for the world, would we, Potty? Potty?
Potty: Rah! [hits Patchy] I'm just here for the buffet. [grabs a fish from the water]
Patchy: Oh, Potty! [grumbles] Give me that! [drops the fish in the boat; he picks it up with his mouth and spits it back in the water] Potty, I told you to leave those fish alone! What do you think you are, a seahawk? [laughs]
Potty: I can't help if I was born a predator. Rah!
Patchy: Oh, Potty. I guess you're right. Can you ever forgive me? Shake. [Potty bites his fingers] Oh! Oh! Oh! [groans]
Potty: Now I can. Rah!
Patchy: Oh, get out of here! [chuckles as he pulls out a really long telescope] Yep! Whoosh! [dips the telescope in the water, laughs, and sees SpongeBob and the gang throwing Sandy a birthday party in Jellyfish Fields] Oh, oh, yeah! I'm gonna save these mental pictures for me grandkids. [chuckles and peeks through the telescope with his other eye] Oh, that's better.
Sandy: Y'all are the best aquatic critter friends a lone star from out of town could ever have.
Patrick: Cake time! [pounds on the table]
[Sandy's birthday cake flies into Patrick's mouth. Patrick swallows the cake whole and licks the icing off his face.]
SpongeBob:[gives Sandy another cake] Don't worry. I always carry a spare.
[Patrick goes to pound the table again.]
Sandy: Oh, no you don't! [lifts the cake in the air] Hoo-hah! Karate slice! Hi-yah! [karate chops the cake into pieces for her friends]
SpongeBob: Enjoy the cake, everybody. I made it special just for Sandy. [eats the cake] Mm.
Squidward: I'm allergic to nuts. Are there any nuts in that?
SpongeBob: Nope, no nuts.
Squidward: Oh, okay. [eats the cake]
SpongeBob: Oh, unless you count "wall nuts."
Squidward: What? [his face swells up]
SpongeBob: I'm pretty sure walnuts are a fruit though, huh?
[Squidward groans. Pearl, Mr. Krabs and Mrs. Puff eat their slices of the cake. Mr. Krabs goes to give Mrs. Puff a piece of his cake.]
Mrs. Puff: Mmm!
[All of a sudden, the ground shakes.]
Mrs. Puff: Whoa—oh—oh—oh—oh! [Mr. Krabs accidentally pokes Mrs. Puff in the eye with his fork]
[Larry does some weight-lifting while eating some cake.]
Larry:[feels the ground shaking] Huh? Whoa! [falls over]
Sandy:[feels the ground shaking] Whoa! [falls over and gets up] Tex Ritter! You don't see that everyday. [she runs over to a volcano, but as she gets closer, a spooky, green-glowing moon comes out from the top] Huh?
Everyone: Ooh! Pretty!
Larry: Last time I saw a moon that big, it was in a locker room. [chuckles]
SpongeBob: Since when is the moon so green?
Patrick:[chuckles and munches on some cake] Everyone knows the moon is made of cheese, SpongeBob. [swallows some cake] It's just been up there so long, it's getting moldy. [his pupils turn green] Oh, but I'd still eat it. [eats some more cake]
Sandy: That ain't the moon, guys. The real moon comes out at night, remember? Something's fishy going on here.
Dad:[laughs as he plays ball with his family] Attagirl, Sissy!
Daughter: I got it, Dad!
Billy: Look out, Mom!
Mable-Monica: Hey, kids, check out that cool, glowing rock in the sky.
[The green moon flies over the family. However, something unexpected happened. When the green moon's light touches them, their bodies glow green and one by one, they transform into realistic fish. Then they eat the ball.]
Sandy: You don't see that everyday. Did you see that, SpongeBob? Sponge...Bob?
[All of Sandy's friends are completely brainwashed by the green moon's light. The green moon flies over Frankie Billy, who is flying a kite.]
Frankie Billy: Huh?
[The green moon transforms Frankie Billy into a realistic fish. Then he eats his kite. Sandy gasps and rubs her eyes in shock.]
SpongeBob and Patrick:[both chanting] Green cheese! Green cheese! Green cheese!
[The green moon flies over SpongeBob and Patrick and they both transform into realistic sea creatures. SpongeBob is transformed into a realistic sea sponge while Patrick is transformed into a realistic starfish.]
Sandy: SpongeBob? Patrick? [SpongeBob and Patrick crawl around, eating little bugs in the grass; Sandy gasps and runs towards her friends] Everyone listen to me! Get away from the light! The light is bad! Run for the shade!
[But it was too late. Sandy's friends completely immobilized by the green moon and they won't move an inch.]
Mrs. Puff: So romantic. [shoves Mr. Krabs' in the shoulder]
Mr. Krabs: Oh-ho!
Mrs. Puff: Eugene-ikins, give me some sugar.
Mr. Krabs: I'm always a sucker for a good smooch.
[But before they kiss, the green moon flies over them and it transforms them into realistic sea creatures. Mr. Krabs is transformed into a realistic crab while Mrs. Puff is transformed into a realistic puffer fish. Mr. Krabs pinches Mrs. Puff in the lips with his claw. Mrs. Puff puffs up and sends Mr. Krabs flying to a coral reef. Mr. Krabs crawls underneath the coral reef to hide.]
Pearl:[talking to one of her friends on the phone] Yeah, walk outside and check out this awesome moon. [takes a picture with her phone]
[The green moon flies over Pearl and it transforms her into a realistic sperm whale.]
Phone: Hello? Hello, Pearl?
[Pearl swallows her phone. Larry is looking at the green moon while doing some weight-lifting. The green moon flies over Larry and it transforms him into a realistic lobster. It looks as though if Sandy is the only sole survivor of the green moon's effect. The green moon slowly turns its light towards Sandy.]
Sandy: No! Not me! [screams as the light passes over her, but to her surprise, the green moon doesn't seem to effect her at all] Huh? I guess it only effects sea creatures, but I still don't get why that green moon is turning everyone into wild swimming fish? [gasps] Am I the only one left?
[Sandy hears a toilet flushing from the restrooms. It turns out that the only friend who hasn't been transformed under the effects of the green moon is Squidward.]
Squidward: Oh, whoever used that restroom last was an animal! [Sandy grabs Squidward just before the green moon can get him] Hey, put me down! Sandy! What are you doing? Ow! That hurts! [Sandy shoves Squidward under a rock to protect him from the green moon; he groans] What is the meaning of—
Sandy: Get in the shade! [shoves Squidward underneath with her foot just as the green moon flies by]
Squidward: I demand an explanation!
Sandy: I'm getting one right now, Squidward! [dials a number on her communicator]
[The communicator contacts the French Narrator, who is traveling in a submarine.]
French Narrator:[answers the phone] Hello? French Narrator speaking.
Sandy: Hey, Frenchy! It's me, Sandy!
French Narrator: Ah, Sandy Cheeks. [holds up a picture of Sandy] How is it hanging?
Sandy: Oh, it's not hanging too good, Frenchy. You see, there's this—
French Narrator: Don't say another word. I have been monitoring the behavior of the green moon all day. It is called Neptune's Moon. Every 100 years, it de-evolves everyone in Bikini Bottom into primal fish for two hours.
Sandy: Two hours?
French Narrator: Until it falls into another volcano and is extinguished. [gives a demonstration of Neptune's Moon and his experiment splatters green goo on his helmet]
Sandy: I knewed it was nature, dagnabit! That's a relief. So I just have to keep Squidward in the shade for a couple of hours. [Squidward becomes easily frightened when he sees wild fish eating each other] Whew! Thanks, Frenchy.
Squidward:[screams and crawls out from under the rock] I'm going home to hide under the covers! It's every cephalopod for himself! [he idiotically runs toward Neptune's Moon]
Sandy:[gasps] Frenchy, I gotta call you back! [runs after Squidward] Squidward, you have to stay in the shade!
[Squidward trips and falls over. He is cornered by a carnivorous fish.]
Sandy: Squidward! No!
[Just as the carnivorous fish was about the eat Squidward, Neptune's Moon flies over Squidward and it transforms him into a realistic giant octopus. Squidward eats the fish and rushes towards Sandy.]
Sandy: O.M. Jehoshaphat! You don't see that everyday. [dodges Squidward's tentacle and hops on the jellyfish] My friends are gonna be lunch if I don't think fast! [gets stung, jumps down, and grabs a net; Squidward destroys the picnic table] SpongeBob! Patrick! [scoops up SpongeBob and Patrick with the net] Mrs. Puff! Mr. Krabs! [scoops up Mrs. Puff and Mr. Krabs with the net] Larry! [picks up Larry; Mr. Krabs pinches Sandy's tail with his claw] Yeeouch! [throws Larry in the net and runs toward Pearl] Look out, Pearl! I'll save you! Yee-ha! [jumps onto Pearl's tailfin; Squidward nearly bites Sandy, but Pearl manages to swim away; Sandy laughs in relief now that her friends are safe] Like busting a bronco! Yee-ha! [Pearl swims away from Jellyfish Fields; Sandy rips the net off the stick and holds it by her tail; Pearl breaks the Bikini Bottom sign as she continues swimming] Whoa—oh—oh—oh! [Pearl flips her tail, causing Sandy to tumble towards the blowhole] Not the blowhole! [Sandy falls in the blowhole; Pearl blasts Sandy out and send her crashing underneath a flying airplane; the passengers and crew of the plane are transformed into realistic fish due to the effects of Neptune's Moon; Sandy falls on Pearl's back and the plane crashes offscreen, killing the passengers and crew onboard; Pearl then swims over Bikini Bottom, where the citizens are looking directly at Neptune's Moon] Hey! Everybody! The light is bad! Stay away from the light!
Highway Speed Officer: License and registration, please?
[Nat Peterson takes out his driver's license. Just as the officer was going to write up a ticket, Neptune's Moon flies over them and transformed Nat and the officer into realistic fish. Pearl swims away from Bikini Bottom and swims towards the surface.]
Sandy: Hold your breath, creatures!
[On the surface, Patchy sees Pearl heading straight towards him through his telescope.]
Patchy: Uh-oh! [panicked screams] Whale! Stroke! Stroke! Stroke! [rows his boat out of Pearl's way; Pearl leaps over Patchy and Potty and jumps back into the ocean, splashing water into Patchy's boat] Oh! Oh, Potty! We're taking on water! [starts bailing water] A little help here, please, Potty? [Potty splashes Patchy with a bucket of water] Oh! Get out of here, you fiendish feather duster! Shoo! Shoo! I said, shoo! I'll do it meself. I don't need your help. I'm perfectly fine doing it by meself. [continues bailing water]
[Pearl swims downward from the surface and swims over Bikini Bottom. Then she swims toward's Sandy's treedome.]
Sandy:[screams] Here's where we get off! [Pearl drops Sandy and her friends off at the treedome and Sandy jumps off her back] Thanks for the lift, Pearl! Don't you worry. Nobody's going to eat you guys on my watch. [Mr. Krabs pinches Sandy's hand with his claw] Ow! [inside her treedome, Sandy puts SpongeBob, Patrick, Mr. Krabs, Mrs. Puff and Larry in a little aquarium; she feeds them fish food] Dinner time! Come and get it! [her transformed friends eat the food] This is so fascinating, Frenchy. Tell me more about my fishy friends. Oh, wait. I'll put you on speaker phone. [puts her communicator on speaker phone]
French Narrator:[about Larry] Ah, the lobster. The cockroach of the sea. Skittering across the ocean floor, the lobster sheds its skin once a week...[Larry molts his shell and eats it] And then eats it.
Sandy: Now that's what I call recycling, huh, Frenchy?
French Narrator:[about Mr. Krabs, who is eating garbage] Ah, notice the scavenger crab eating garbage [about Mrs. Puff] unaware he is being stalked by his natural predator, the puffer fish.
[Mrs. Puff stalks Mr. Krabs and eats him.]
Sandy: Oh, no, you don't.
[Mr. Krabs pinches Mrs. Puff's mouth with his claw.]
Mrs. Puff: Ow! [she and Mr. Krabs fight, but they are scooped out by Sandy]
Sandy: I knew I was gonna have to separate you two. [pulls Mr. Krabs out of Mrs. Puff's mouth] You're welcome, Mr. Krabs. [giggles, but gets pinched by Mr. Krabs again] Ow! [Mr. Krabs pinches her really hard] Yeowch! [throws Mr. Krabs and Mrs. Puff back in the aquarium; Mrs. Puff stalks Mr. Krabs again]
French Narrator:[about Patrick as he ejects his stomach from his body to eat kelp] Ah, observe how the hungry sea star ejects his own stomach from his body in order to eat his meal, [about SpongeBob as he filter feeds bacteria] where the primitive sea sponge filters nutrients and oxygen from bacteria particles.
[Bacteria scream as they are being filtered in SpongeBob's body. SpongeBob laughs as Sandy takes a picture.]
Sandy: SpongeBob is never gonna believe this.
[Suddenly, a shadow looms over Sandy. It turns out that the shadow is Squidward, who is now hovering over the treedome. Sandy whimpers in fear.]
French Narrator:[about Squidward] Ah, the giant octopus. One of the largest predators on the ocean floor.
Sandy: Texas toast! It's a good thing my treedome is made of ten tons of pressure proof glass, huh, Frenchy?
French Narrator: Oui, Sandy, that is true, but, unfortunately, the poisonous and highly intelligent octopus can also cut through hard bedrock with its beak.
[Squidward drills a hole through the treedome with his beak.]
Sandy: You don't see that everyday! Squidward, no!
[But it was too late. Squidward broke through the treedome and floods the entire place. Sandy grabs her helmet and puts it back on. Squidward breaks the entire treedome and goes to eat his friends. Sandy scoops up SpongeBob, Patrick, Mr. Krabs, Mrs. Puff and Larry, then hides them inside her tree.]
Sandy: Whoa! [almost gets hit by Squidward's tentacle as it wraps around the tree] Oh! [gets grabbed by Squidward's tentacle and is held in the air; Squidward breaks through the door with his beak] Hi-yah! [her hand breaks] Aah, hominy grits! [Squidward goes to eat his friends]
French Narrator: Ah, the battle for the survival of the fittest rages on in the animal kingdom.
Sandy: My friends! My tree!
French Narrator: Sandy, you must remember, who is the natural enemy of the octopus?
Sandy: That's a great idea. [breaks herself free and uses her tail to create echolocation]
French Narrator: Using her versatile tail, the Texas Land squirrel calls out to the natural enemy of the octopus.
Sandy: There she blows, y'all!
French Narrator: The whale.
[Pearl bellows as she comes to the rescue. Pearl swims up to Squidward.]
Sandy: Sick 'em, Pearl! Sorry, Squidward!
[Pearl and Squidward go into an all out battle for each other. SpongeBob, Patrick, Mr. Krabs, Mrs. Puff, and Larry crawl over to Sandy for protection. Squidward pokes Pearl in the eye and Pearl whacks Squidward with her tail. Squidward tangles Pearl with his tentacles, but Pearl blows water at Squidward through her blowhole.]
Sandy: Ooh! Ohh!
[Pearl begins gnawing on Squidward. At that moment, Sandy's watch rings.]
Sandy: Oh! Two hours is up? Thank goodness.
French Narrator: And so we bid a fond adieu to Neptune's Moon as it descends back into the Earth from whence it came. We will see it again in 100 years. [Neptune's Moon slowly descends downwards and enters another volcano; foghorn blows] Goal!
[Mr. Krabs and Mrs. Puff fight each other again. However, now that Neptune's Moon is gone, they both revert themselves back into their regular forms. But unfortunately, the effects of Neptune's Moon also caused their respective clothing to dissolve into nothingness, thus leaving them naked. Mr. Krabs and Mrs. Puff cover themselves in embarrassment and run off. Larry reverts back to his regular form as well. But he is also naked. He picks up a flower and uses it as a loincloth. Then he walks away. Pearl and Squidward continue fighting above Sandy's treedome. They both revert back to their regular forms. However, they're also naked as well. Pearl spits Squidward out from her mouth.]
Squidward: What is going on here? [gasps] My clothes! [screams and runs away]
Pearl:[screams and runs away as she is naked] No!
[SpongeBob and Patrick revert back to the regular forms, but they're also naked as well.]
[SpongeBob pulls himself off of Sandy's suit. Patrick giggles and falls off of Sandy's helmet. SpongeBob looks around and sees Sandy's treedome destroyed.]
SpongeBob: Um, Sandy, how come your treedome is broken and everyone's naked?
Sandy: Well, SpongeBob, let's just say this has been the most interesting birthday I ever had.
French Narrator: And, of course, Neptune's Moon is always followed by Neptune's Sun.
[The ground shakes. Neptune's Sun comes out of a volcano and shines its light on Sandy. The light then transforms Sandy into a realistic land squirrel. It appears that Neptune's Sun only effects land creatures while Neptune's Moon only effects sea creatures. Sandy chitters and crawls around inside her suit.]
SpongeBob and Patrick: You don't see that everyday. Jinx! Buy me a patty! [both laugh as Sandy chitters]
[The scene changes to Bikini Atoll.]
French Narrator: Ah, Bikini Bottom. Teaming with life and naked mysteries. This next whale song is going out to my favorite squirrel. Sandy, happy birthday.
Sandy:[as she water skis across the ocean] Yee haw! Whoo!
Patchy: Ooh, Potty, I never thought it'd end up like this, brunch for a shark.
Potty: I guess this is it. Good-bye, Patchy.
Patchy: Good-bye, Potty. [crying]
[A shark fin pops up from the surface. Patchy and Potty scream in fright. But it turns out to be the French Narrator.]
French Narrator: Hello!
Patchy: Frenchy, you surprising scallywag! Get—What are you doing here?
French Narrator: Ah, Patchy the pirate, I just swam back to warn you about Neptune's Sun, but it's too late. Au revoir. [leaves]
Patchy: Bye. Neptune's Sun? [Suddenly, just as the French Narrator said, Neptune's Sun flies over Patchy and Potty; Patchy whimpers and screams] What's happening?!
[Neptune's Sun transforms Potty into a pterodactyl while Patchy transforms into a primitive cave man. Patchy and Potty look at each other and notice they are different from before. Patchy grunts in confusion. But Potty thinks Patchy is a Krabby Patty.]
Potty: Mm, yummy. [laughs as he grabs Patchy and flies away with him; ending the episode]