Ash's Adventures of The Little Mermaid: Ariel's Beginning is the first Pokémon/Little Mermaid crossover film by Daniel Esposito. It will appear on Google Drive in the near future.
King Triton and his wife, Queen Athena, rule over the underwater kingdom of Atlantica, which is filled with music and laughter. They have seven young daughters, the youngest of whom is Ariel. The merfolk are shown relaxing in a lagoon above water, and Triton gives Athena a music box. Suddenly, a pirate ship approaches. Everyone escapes except Athena, who is crushed by the ship when she tries to save the music box. Devastated by the death of his wife, Triton throws the music box away and bans music from the kingdom.
Ten years later, Ariel and her six older sisters live under a strict routine maintained by their governess, Marina Del Rey and her assistant, Benjamin. Marina hates being the girls' governess and longs to be Triton's attaché, a job currently filled by Sebastian thecrab. Ariel hates their current lifestyle, which brings her into arguments with her father. One day, Ariel encounters Flounder, a youngfish whom she later follows to an underground music club. She is overjoyed by the presence of music, and is shocked when she sees Sebastian performing there. When her presence is revealed, the entire band stops playing and hides, believing Ariel will tell her father about them. Ariel sings a song explaining her love of music and the remembrance of her mother and she joins the club with an oath.
Ariel returns to the palace, and her sisters confront her over her disappearance. She explains where she was, and the following night all seven girls go to the club to have fun. Marina finds them, she later reports their activities to Triton, who destroys the club with his trident. Sebastian, Flounder and the band are sent to jail, while Marina gets the job as the king's majordomo. Triton locks his daughters inside the palace, resulting in Ariel asking him why music is forbidden, but he refuses to answer and angrily shouts, "I will not have music in my kingdom!". Distraught, Ariel argues that Athena wouldn't have wanted music forbidden and swims to the bedroom, with her sisters following. That night, she leaves Atlantica and frees the jailbirds. Sebastian leads them to a deserted place far from the palace where Ariel finds Athena's music box, as Sebastian hoped. Ariel and Sebastian decide to return to Atlantica to bring the music box to Triton, hoping that it will change his mind, as he has not remembered how to be happy after Athena's death.
On the way back, they are confronted by Marina and her electric eels. Marina wants to stop them so she will retain her position of "power", and struggle ensues. It ends when Marina barrels towards Sebastian, but Ariel pushes her away, getting hit in the process. Triton arrives in time to witness this, and blames himself. He sings the lyrics of "Athena's Song", and Ariel wakes up. The film ends with Triton restoring music to Atlantica and appointing Sebastian as Atlantica's first official court composer, much to everyone's glee. Everyone rejoices except Marina, who is sent to jail.
Inside the prison cell, Benjamin, who was also arrested for knowing about Marina's plan, asks Marina if she's learned her lesson. She begrudgingly says yes, and Benjamin asks Marina to dance with him. They begin to dance inside the cell.
- Kronk, Zhane, Korra, Mako, Bolin, Asami Sato, Jack Skellington, the Mighty Morphin Power Rangers, Team Rocket (Jessie, James, and Meowth), Oogie Boogie, The Crime Empire (Joker, Harley Quinn, Two-Face, The Penguin, Negaduck, Megavolt, Quackerjack, Bushroot, and The Liquidator) are guest starring in this film.
- Team Rocket, Oogie Boogie, and The Crime Empire will work for Marina del Ray in this film.
- Kronk has met Sebastian before in Simba, Timon, and Pumbaa's Adventures of The Emperor's New Groove.
- The storyline continues in Ash's Adventures of The Little Mermaid (TV series), Ash's Adventures of The Little Mermaid, and Ash's Adventures of The Little Mermaid II: Return to the Sea.