|“||Aye, Captain. 2-1-0-0.||„|
He is a gray octopus-resembling alien bearing two long tentacles for each of his arms and legs. He served as the helmsman to Captain Amelia, though he may have maintained his position as such during the mutiny. During the voyage, the ship encounters a supernova. Jim (while securing lifelines of all pirates) saves Silver from falling just in time. The supernova then devolves into a black hole, where Arrow falls. The burst of shock waves and maximum engine power enable Amelia to pilot the ship to safety. Amelia mourns the loss of Arrow, and suspects Jim of failing to secure the lifelines, while Arrow's line was actually cut by Scroop. Meanwhile, Turnbuckle and the pirates corner the group here; using a back door, Jim, B.E.N., and Morph return to the ship in an attempt to recover the map. He is one of the last two pirates (the other being Blinko) to die in the film; during the collapse of Treasure Planet, as he and Blinko instantaneously struggled to escape with their ill-gotten gains, they were caught in the waterfall of gold coins and fell into the lava-filled crevices to their deaths.
- "Aye, Captain. 2-1-0-0."
- "Aye, Captain."
- "We're being pulled in! Ohh!"
- "Poor boy." (his last words)
- In Treasure Planet: Battle at Procyon, a continuity error is made as in the game, he is still alive and tells Jim "beware" while handing him a piece of dark matter, but in the movie, he falls to his death with Blinko at the planet's exploding core.
- Turnbuckle's voice actor is Rodger Bumpass, the same actor who also played Squidward Tentacles from the SpongeBob SquarePants franchise.