Over the ocean, near a European kingdom, a royal ship was taking a trip. On the ship were Princess Mabel Pines and her twin brother Prince Dipper Pines. Mabel was next in line for the throne due to being older (only by five minutes, which Mabel never let Dipper forget much to his annoyance). Dipper didn't mind not inheriting the throne, he was more of an explorer than a ruler anyway. Besides, his love of knowledge allowed him to learn so much that Mabel made him her future advisor. Dipper was very honored by this role, and vowed to never take it lightly.

SAILORS:
I'll tell you a tale of the bottomless blue
And it's hey to the starboard, heave ho
Look out, lad, a mermaid be waiting for you
In mysterious fathoms below

"Isn't this great?" Mabel gazed out towards the sea with her pet pig Waddles. "The salty sea air, the wind blowing in your face."

Waddles oinked with agreement.

"Perfect day to be at sea." Mabel then turned to Dipper...who was over a rail.

"Oh yes, delightful." Dipper said dryly, obviously seasick.

"I told you not eat such a big lunch." Mabel shook her head.

"I was hungry..." Dipper muttered.

"A fine strong wind and a following sea." A sailor remarked as he tied down a rope. "King Nereido must be in a friendly-type mood."

"King Nereido?" Mabel asked with confusion.

"Why ruler of the merpeople lass." Another sailor said as he started tossing fish out of a net and into a barrel. "Thought every good sailor knew about him."

"Oh, merpeople." Mabel scoffed as she petted Waddles. "I can't believe you guys think they exist."

"I dunno Mabel, I've read about them and there have been loads of sightings in the past." Dipper shrugged, finally having recovered.

"Come on bro, half fish and half human?" Mabel chuckled. "What nautical nonsense."

"It ain't nonsense it's the truth!" The second sailor retorted, shaking a fist at Mabel. "I'm telling you down in the depths of the ocean there-"

He got interrupted when the fish in his hand broke free and slapped Dipper repeatedly in the face before diving into the ocean.

SAILORS:
Fathoms below, below
From whence wayward Westerlies blow
Where Nereido is king and his merpeople sing
In mysterious fathoms below

The fish looked back up at the boat and let out a huge breath of relief. He then started to swim away. He continued swimming for a long while...and later on merpeople started swimming with him. They all swam towards a magnificent palace, where Nereido lived. All the merpeople and fish took their seats in a theater. Fish with trumpets for noses sounded a fanfare as a messenger seahorse arrived. He cleared his throat.

"His royal highness, King Nereido!" He announced.

Nereido swam into the theater in a carriage pulled by three dolphins. Everyone cheered as he went up to the chandelier and lit it with his triton.

"And presenting the distinguished court composer: Horatio Thelonious Ignacious Crustaceous Jesus." The seahorse then announced.

Jesus, or Soos as he was better known, swam in on a smaller carriage pulled by two large fish. The large fish got a bit excited at first but Soos was able to regain control and they swam to Nereido.

"I've been looking forward to this Soos." Nereido smiled.

"Oh your majesty, this will be the finest concert I have ever conducted." Soos smiled proudly as Nereido entered his seat on the balcony. "Your sons, they will be spectacular!"

His fish got excited again and he and his carriage ended up upside down.

"Yes, especially my eldest Mermando." Nereido chuckled.

"Yes." Soos grunted as he righted his carriage. "He has the most wonderful voice, and is really good with a guitar as well."

He then flicked the reigns and his fish swam towards the orchestra pit.

"If only he'd show up to rehearsals once and a while..." Soos then muttered to himself.

The lights went out and a spotlight shone on Soos as he landed on his spot. He straightened his shell and then pulled out the sheet music. After setting it up he started the music. The curtain of bubbles opened and three giant clam shells appeared on stage. Two mermen appeared out of each shell, revealing six total.

NEREIDO'S SONS:
Ah, we are the sons of Nereido
Great father who loves us and named us well
Montego, Manuelo, Mariano, Mateo, Macario, Milagro

A new clam shell suddenly appeared on stage.

NEREIDO'S SONS:
And then there is the youngest in his musical debut
Our seventh little brother, we're presenting him to you
To sing a song Soos wrote, he has a charming alto
He's our brother, Merman-

They suddenly stopped singing, and the music stopped as well. The new giant clam shell was empty. Everyone gasped as Nereido became furious.

"MERMANDO!" He yelled.