Brian and the Eeveelution Family's Adventures of The Little Mermaid: Ariel's Beginning

Brian and the Eeveelution Family's Adventures of The Little Mermaid: Ariel's Beginning is the first upcoming Family Guy/Eeveelution/The Little Mermaid crossover to be made by Hiatt Grey.

Plot
King Triton and his wife, Queen Athena, rule over the underwater kingdom of Atlantica, filled with music and laughter. They have seven young daughters: Attina, Alana, Adella, Aquata, Arista, Andrina and the youngest of whom is Ariel. One day, while the merpeople relax in a lagoon above water, Triton gives Athena a music box. However, a pirate ship approaches. Everyone escapes except Athena, who is killed by the ship when she tries to recover the music box. Triton becomes devastated by his wife’s death and throws the music box away, permanently banning music from Atlantica.

Ten years later, Ariel and her 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 the crab. Ariel is frustrated by their current lifestyle, which brings her into arguments with her father. One day, Ariel encounters Flounder, a young tropical fish 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 the girls go to the club to have fun, Marina finds them and she later reports their activities to Triton, who destroys the club with his trident. Sebastian, Flounder and the band are sent to prison, while Marina gets the job she wants. Triton confines his daughters to the palace and Ariel says that Triton wouldn’t have hated music if her mother hadn't wanted music forbidden. She swims to the bedroom, with her sisters following, and everyone is unhappy, aside from Marina. That night, Ariel frees her friends and leaves Atlantica. Sebastian leads them to a deserted place far away from the palace where Ariel finds Athena's music box, as Sebastian hoped. In the kingdom, Marina happily talks to Triton about her new job, but one of Ariel's sisters informs Triton that Ariel is not in Atlantica, while Triton orders his guards to find her, angering Marina. In her lair, Marina tells Benjamin that she releases her electric eels from the dungeon. Marina is about to finish the job to have Sebastian killed and Ariel eliminated from the palace. Ariel, Flounder, 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 died.

On the way back, they are confronted by Marina and her eels. Before music is restored back into Atlantica, the final battle begins when Ariel is banned from Atlantica by Marina. Marina wants to stop them so she will retain her position of power, and a struggle ensues. Flounder and Ariel are rescued from Marina's electric eels by the band. While Triton arrives in time seeing that Ariel has helped the band defeat the eels by having them tangle themselves. Marina barrels towards Sebastian and tries to kill him, but Ariel pushes her away, getting hit in the process. Triton witnesses the incident and blames himself. He sings the lyrics of "Athena's Song", and Ariel recovers. Triton apologizes to her for not listening to her and sends her home to the palace before he orders his guards to place Marina under arrest. On the next day, thanks to Ariel, Triton restores music to Atlantica and appoints Sebastian as Atlantica's first official court composer, much to everyone's delight. Everyone, including Ariel and her sisters and their friends Flounder and Sebastian, rejoices except Marina; who is sent to jail.

Trivia

 * The Griffin Family, Glenn Quagmire, Cleveland Brown, Joe Swanson, Little Bear, Duck, Cat, Owl, Hen, Emily, Lucy, and Mermaid guest star in this film.
 * The storyline concludes in Brian and the Eeveelution Family's Adventures of The Little Mermaid.