A/N: So I was making pumpkin soup one night when it suddenly occurred to me that Bruce Banner is basically a pufferfish. Which, of course, makes Tony a merman. Shenanigans and bad writing ensue. (Now with even less spelling/grammatical errors!)

Prologue

A colossal storm had sunk the cargo ship two days ago, pushing it down onto the seabed where it now balanced half on the sand, half over a crevasse. All the crew had miraculously escaped, leaving a precious piece of cargo aboard and free for the taking.

Chapter 1

Tony swam around the workbench, his tail twitching with excitement. "It's perfect, man! The shipwreck's iron-ore mass fit beautifully into your calculations. All we need now is to stabilise the starboard's weight over the crevasse in the ocean bed, get JARVIS to double-check the ship's demagnetisation status, and -" he poked Bruce in the belly with his ball point pen – "we're set."

Bruce frowned and tried to rub off the pen's ink mark with his fin. "Presuming that the demagnetisation actually works this time, that the sand's PH levels aren't too high - "

"It'll be fine!" Tony interjected.

Bruce ignored him, and carried on with the list, "… that the crevasse doesn't expand and swallow not only the ship but also you, that there aren't any sharks… oh, and that we can actually get passed the Imperial Sea-Horse Guards and into the area in the first place."

"Minor details," said Tony flippantly, waving his hand in a way that was clearly meant to stop Bruce from worrying but which only served in making the pufferfish more frustrated. "And, anyway, last night JARVIS was able to confirm that the sand's PH won't affect the demagnetisation at all."

Bruce narrowed his eyes in distrust.

The merman then reached under the bench to show Bruce a container he had found. The box was labelled, 'Sugar Cubes'.

The pufferfish laughed.

"Sea-horses aren't the brightest creatures in the ocean," Tony said with grin and a swish of his shiny blue tail.

Bruce twirled gently from side to side, a gesture seen frequently among fish to signal their exasperation. (Creatures with necks such as merpeople and humans had long subdued this gesture into the mere twirling, or shaking, of their heads.) "Well, that takes care of the guards, at least. What do you plan to do with any sharks?"

"Well," considered Tony, "an appearance of one would be extremely unlikely, given the circumstances. But, if there are any, I figure you could just take of them, hey big guy." He poked Bruce in the stomach again, trying to get a reaction.

Bruce just glanced at him, unimpressed.

"You're no fun," mumbled Tony.

"Sir," JARVIS interrupted, "I have compared Mr Banner's calculations against the sand, and can confirm that the PH is indeed too high for –"

"Thank you, JARVIS," Tony said loudly," for your impeccable timing, as always."

"You're most welcome, sir," JARVIS replied.

After a moment of silence, Bruce sighed. "So after four sleepless nights of intense preparation, we haven't achieved a thing."

"Don't be such a pessimist, Brucey. We have achieved THIS!" Tony lifted up a sheet of paper from the desk and brandished it over his head with excitement.

"Tony, that's a poster of a topless mermaid surrounded by squid," Bruce deadpanned. If he was able to cross his fins, he would have.

"What? Oh," said Tony, looking at the paper dejectedly. "Right. But you've gotta admit, there's something about all those tentacles..."

Bruce cleared his throat.

"Sorry." Tony hastily stashed the poster into a nearby folder. "What we have achieved…" he looked around wildly, "is…" he hurriedly leafed through the many diagrams and graphs that littered their workbench, "is…" he picked up a piece of parchment filled with Bruce's doodling and scribbles, and grinned, "is THIS."

A pause.

"That," Bruce said slowly, "could work."