One piece, but they get sucked into a whirlpool all the way into the Mariana trench.

One Piece, not from the show scenes (I think) has all members of the crew, plus a pick me girl, named Nuka.

Straw Hats (Made) | (Not made yet): Heart Pirates, Whitebeard Pirates, Red Haired Pirates

Nuka- Shes 5'3, she's got a bratty attitude, hates women, claims to be better than the rest of the women, but acts like an angel towards Luffy, Zoro, Sanji, and Franky, everyone else is just an extra. She's got a small waist, C cup bra size, good thighs, tight ass, she's wears a white skimpy/proactive skirt, pink thongs that show when she bends over, no bra, wears a tight white blouse that's open and tied tightly to press her boobs together and show everything off, but it's see through when wet, and she wears white heels, and she hal long blonde hair down to her hips, blue eyes, pink nails, and a butterfly tattoo on her right breast, on her sternum, and she thinks that will make Luffy fall for her, and she plays with Sanji's feelings so he does stuff for her own benefits. She often tries to be like Zoro's childhood best friend who died, wanting Zoro to fall for her. Her weapon is an aphrodisiac laced with poison that drugs them into sleep, and her devil fruit is Lust Lust, anytime someone is lustful, she knows, pretty lame. Her bounty is 5,000. Not much compared to everyone else.

Scenerio #1: The Sunny is sucked into a whirlpool and carried through a glowing underwater tunnel into a massive treasure-filled cave.

Scenerio #2: The Sunny is pulled into a mysterious underwater tunnel leading to a hidden Mermodi territory. They emerge in a massive treasure-filled cave, Jinbei knows about the Mermodis.

Scenerio #3: The Sunny is pulled into a mysterious underwater tunnel leading to a hidden Mermodi territory. They emerge in a massive treasure-filled cave, Jinbei knows about the Mermodis, Nuka is in this one.

Information about the creature in the second and third Scenerios:

Mermodis are made up of Sea Kings, dragons, humans, snakes, and mermaids. They are 20% human, 25% snake, 15% dragon, 5% mermaid, and 35% sea king. They are cousins with the largest and most aggressive breeds of sea kings. They're known for hoarding treasure, mostly pearls, gems, gold, diomands, amethyst, sea prism stones, and often having a stash of devil fruits as the legends say. Apparently, pure colored mermodis have golden or diamond blood, slightly mixed colored mermodis have emerald or silver blood, mixed colored mermodis have Larimar or Pink Coral blood. Mermodis are exceptionally rare, and they come in all different shapes and sizes, but they all have a long serpent like naga tail with a large or small fin on one side of their tail tips, the fins are random based on their type, gills on the hips and neck, serpent tongues, and sharp claws. They often bury themselves in treasure in their territory, but they have human forms too, which are entirely unpredictable to humans. Their personalities are very human like, and it's extremely hard to catch one, since they're twice as fast as mermaids, not to mention they're worth three fortunes, and that's starting off with the weakest mixed colored ones. People often drain their blood cuz it hardens quickly, and can be sold once hardened, that's why they are almost extinct now. They can mate with humans, but most humans only want their blood, and due to their disappearances, mermodis have become hostile after centuries of being hunted down, and they went into hiding, they're amphibian, so they can live on land and in the water. They were mostly hunted throughout the blank century, so not much is known about them any more since the marines tried to kill them all off just like pirates. Their bodies can adapt to any living environment, and their upper humanoid half skin is made from armored dragon scales, but it's got normal human softness and texture, but their snake like tails are made from dragon scales and sea king scales. A single scale from one of these based on the color and type, can cost a small fortune if it's a pearl scale, but it can cost three times as much if it's a pure diamond scale.