The Mystery of the Dark Squid is a GoAnimate Film by Sophie the Otter.
Sophie the Otter contacts Igor, WilliamWill2343, James the Animator and the others to take a journey through the GoAnimate Ruins in a lush valley not far from GoCity. While adventuring through the ruins, they encounter dangers such as bony enemies named the Tentiskulls (Which are short human skeletons with tentacles for arms and legs) blocking the way to an underground river with an ancient Chinese paddleboat, moving walls, ceilings and floors, and a labyrinth filled with obstacles such as spikes and pits of lava.
In the heart of the ruins, they see an enormous creature made out of dark matter resembling a giant squid named Dark Squid, which can absorb darkness to increase its size. It engages the team to an ultimate battle royale as PB&J transform into their alter-egos. At the end, the giant squid's eye, which supports the formation and structure of Dark Squid, has been detonated and its body dissipates, brightening up the heart of the ruins.
The Dark Squid has been actually revealed to be HomerTheGuyProHD. Homer states that he did this just to seek revenge on the heroes. However, the team denies the statement and shoves Homer down the abyss, leading to a pit full of Black Widow Spiders.
- Kayla as Sophie the Otter, Shauna, and Jelly
- Paul as Igor the Mii and Alex Kimble
- Young Guy as James the Animator, SERGEANTCOMMANDARMY, and PaperPizza
- Dave as WilliamWill2343
- Duncan as the Tentiskulls
- Scary Voice as the Dark Squid
- Steven as HomerTheGuyProHD
- Eric as Carkle the Animatronic, Robbie, Swordlord P, and Optimus500050
- Kimberly as Peanut Otter and G.I. Jelly
- Shy Girl as Baby Butter Otter/Kick-Butter
- Brian as Samuel
- Kate as Joey King
[We see the words PB&Jotterisnumber1 Presents, followed by the title of the film]
[We cut to Sophie's room]
Sophie: "I want to discover something new. I better contact my friends first, though."