A/N: Hi.

So, this is a story that you may have seen before by the name of 'The Great Epic MultiCrossover Fic Of DOOM!' or 'Maggie & Rachel's Epic MultiCrossover Fic Of Doom!' or even 'Phineas & Ferb's Underwater Adventure under the account 'RubberDucky113,' or my old username 'NoStairwayDENIED.'(Sorry, I have a bad habit of changing names/titles.) It's exactly the same, I just moved this to a joint account between the five of us that are writing. Nothing has changed from the original except the fixing of a few typos. My account is still alive and well, if you read any of my other stories.

A/N: Hey everyone! This story is a little thing that my Harry-Potter-Impaired friend Rachel wrote and, since she doesn't have a FanFiction account, I told her I would publish it for her. I changed it a little from the original, so i guess you could say we're writing it together. Also, this is going to be a Multi-Chapter Crossover Fic. Unless, of course, she decides to stop right in the middle, which is probably likely to happen, but I'll try to stop her. Also, she's a little insane, so if randomosity insues, don't blame me (although, I am responsible for the Narrator/Isabella conversation.)

Also, I am not sure when the Spongebob part of this Fic comes in, but I am assuming within the next chapter or two, or i will beat my friend with a paper napkin (what? I don't actually want to hurt her, then she won't write at all, I just want to annoy her).

And, Rachel would also like to inform the peoples of the internet that she does not watch Phineas & Ferb anymore and also does not watch Sponge Bob Square Pants anymore, this just randomly popped into her head, thank you very much, and seemed interesting (or so she claims).

Summary: When Phineas & Ferb build a submarine that transports them to Bikini Bottom, Chaos Insues! Rated T for swearing.

Warnings: Umm, swearing? that's all I know of so far. I'll add more ratings later if the need be.

Disclaimer: I own nothing. Nothing Except the slip of paper this was written on and the cup of coffee that I am currently drinking (MWHAHAHAHA...Don't ask...). Phineas & ferb is owned by Disney, David Povenmire and Jeff "Swampy" Marsh. Sponge Bob is owned by Nickleodeon and Stephen Hillenburg. Jaws is owned by Peter Benchley and Steven Spielberg. My friend Rachel owns the plot. I am but a middleman getting the story to you (and occasionally changing it a little without permission from her. Hehehe.)

It was a warm summer day. School got out just an hour ago, and now Phineas and Ferb had the whole day to do whatever they wanted.

Now, Phineas was staring off into space and Ferb was reading a book on underwater life. Then Phineas got an idea:

"Hey Ferb! I know what we're gonna do today!" Phineas started. "We'll make a submarine to see if Jaws exists!"

Yesterday, the boys watched the movie "Jaws" on TV and, even though it was fake, they both agreed that it could happen in real life.

Just as they were going to get up, the back door opened.

"PHINEAS!" Candace yelled as she walked outside, "Don't make any of your crazy inventions today, and if you do, you'll be caught…"

Candace babbled on about haw she was going to the mall with Stacy and how Mom would be home all day today and blah blah blah…

After a while, Phineas just tuned her out.

"Okay?" Candace asked.

Okay what?!?!? Phineas thought. I wasn't listening! Doesn't she understand that no one cares about her petty teenage worries?

Just say something! The little voice in the back of his mind said.

"Okay, we will!" Phineas said.

Candace was confused. She told them that she was going to use all of their birthday money to buy this dress that she wanted at the mall. What kind of an answer is "Okay, we will"?

"So is that a yes?" Candace asked.

"Umm…Yeah sure!" Phineas replied. Ferb glared at him.

Thanks guys! You're the best!" She said, and ran off to their room.

"I don't get it, why did she say thanks?" Phineas asked Ferb.

"Because, she asked us if she could burn all of our money on a stupid prom dress and you said 'yes', you moron!" Ferb replied in an angry tone.

"WHAT?!?! Dammit!" Phineas exclaimed and ran after Candace.

"Candace! WAIT!!!"

But it was too late. Candace had driven off with their $300, headed for the mall.

Just then, Isabella came over.

"Hey Phineas! Whatcha doin'?"

Unfortunately, Phineas didn't hear her and continued rambling on about his money:

"Well, that's just fucking great!" he yelled.

"PHINEAS!!!" Isabella was shocked at at his language, so she slapped him across the face. "DON'T. EVER. SWEAR. Tie him up Fireside Girls!"

By the time Phineas even realized what was going on, he found himself tied to a chair with Isabella standing in front of him with a bar of soap in her hand and arguing with the Narrator.

"Do I really have to clean his mouth out with soap?" she asked in a voice that could definitely be classified as "whiney".

"Yes!" the Narrator exclaimed in an exasperated voice.

"But why?" she asked.

"Because I said so. And also because this is supposedly important to the plot." Said the narrator as if he was talking to a small child, which he sort of was.

"Ugh! Fine!" Isabella said in a defeated yet somehow still whiney voice.

"Good girl! OK, where were we? Oh yes!"

Just then, Isabella exclaimed, " Lets wash the 'dirty' out of your mouth!"

"WAIT!" Phineas yelled.

"Ugh, what is it now?" Isabella asked.

"What flavor is the soap?"

"Oh!" she giggled "Apple!"

"NOOOOO!"

So, whaddya think?

there's only one way we'll know, ya know-

that's right, press the pretty green button.

Also, this won't be updated until at least Monday, seeing as that's when I next have school, what with Thanksgiving and everything.

Oh yeah, Rachel also said that if I don't write R&R, she'll shoot me, and, seeing as I would rather not die anytime soon, I will.

R&R!