Sinker is shown to be greatly offended by the mocking of his fin size compared to the rest of him. He is also incredibly territorial and will claim an entire body of water, sinking any sea vessel that sails in that area.
Experiment 602 was the 602nd genetic experiment created by Jumba with Hämsterviel's funding. He was designed to slice enemy sea vessels in two with his massive, razor dorsal fin. 602 and the other first 624 experiments were deactivated and smuggled to Earth by Jumba during his mission to capture Experiment 626.
All of the experiment pods were released and scattered across the island of Kauai.
At an unknown point after this, Experiment 602 was activated.
Later, Lilo, Stitch, Jumba and Pleakley stowed away aboard a cruise ship, where Lilo intended to warn the captain about Sinker's rampage. However, they got caught and thrown in the brig due to Stitch's horseplay. After the four managed to break out, Jumba hatched a plan to capture Sinker.
While Stitch, wearing scuba gear (and defying his aquaphobia), dove underwater to find Sinker, the latter retreated to a cave until he eventually came out, revealing the diminutive size of his body. Sinker, however, wasn't amused when Stitch laughed at the former's puny size.
Sinker then escaped, but Stitch chased after him and was able to grab hold of his large dorsal fin. Sinker sunk a fishing boat, where two fishermen were catching fish with a net. He then attempted to sink the runaway cruise ship, but Stitch managed to capture Sinker in the ship's anchor and chain.
Shortly after, Sinker was found a one true place at a sushi restaurant, cutting up fish fillets and vegetables with his elongated dorsal fin.
In "Ploot", Lilo tried to convince Sinker to help her defeat Ploot, but he was unable to because he was very busy cutting up food for a large party while Hatha, the other chef who worked there, was sick.
In the film's opening, Sinker can be seen popping his head out of the water and waving hello to Lilo.
Later, the first 624 experiments, including Sinker, were rounded up by Leroy and taken to a stadium to be destroyed. However, Lilo, Stitch, Jumba, Pleakley, Reuben and Gantu arrived before the experiments could be destroyed.
Sinker participated in the following battle between the experiments and the Leroy clones.
The Leroys soon gained the upper hand in the battle, but were defeated when Lilo, Stitch, Reuben and several other experiments performed the song "Aloha ʻOe", which caused the Leroy army to shut down due to the original Leroy's fail-safe.
Sinker made an appearance in the Stitch! anime where Hämsterviel used him along with Slushy to attack a cruise ship that Hämsterviel had lured Stitch onto. It is also revealed that Sinker has a blind spot on his dorsal fin, and he will become immobile if forced into a horizontal position because of his large fin. He also made a cameo appearance as one of the experiments in Hämsterviel's prison cell.
- Sinker is an obvious parody of the titular great white shark from Jaws.
- Sinker's fin is shown to have differences in size, though it is likely a continuity error.
- Sinker is one of the rare experiments to have dark red eyes instead of black ones like most of the rest.
- Sinker's pod color is blue.
- Sinker is described by the experiment computer screen as, "Experiment 602. Primary function: Sinker of enemies' ships."
- Sinker is one of the few experiments to not appear in the group photo at the end of Leroy & Stitch.