Seymour Scales is a light bluish-gray shark and wears an ivory-colored shirt, purple pants, and a red and tan-striped tie. He also has orange hair and eyebrows.
Upon arriving to Mrs. Puff's Boating School, he witnesses SpongeBob in a sad state. When SpongeBob explains himself, he offers him to be his boating teacher for his learning system, "D.R.I.V.E.," which SpongeBob happily accepts with the only requirement being 15 shells needed to sign up.
After SpongeBob pays, he is instructed by Seymour on every step of the D.R.I.V.E course with SpongeBob showing great progress on destructive driving. As the lessons goes, one by one of SpongeBob's friends starts joining the lessons in order to help him through his lesson, with the exception of Squidward who only joined to smash SpongeBob'z boat, with each paying 15 shells each.
When SpongeBob passes the final exams, he is congratulated by Seymour and after a short pictorial, his license is complete. While SpongeBob gives his thanks to his friends, Seymour is ready to leave. However, Mrs. Puff arrives just in time to inform SpongeBob that he was scammed with a fake learning system and license by Seymour. Devastated about the revelation, SpongeBob pursues his phony instructor. However, Seymour already boarded on his boat, ready to run away. Unfortunately for him, SpongeBob finds a similar boat which he rides to destroy Seymour's boat and to apprehend him.
During the pursuit, Seymour tries to stop SpongeBob by throwing various boat parts in an attempt to slow down and destroy SpongeBob's vehicle. However, SpongeBob keeps pursuing Seymour and eventually is able to destroy the latter's boat instead. After the defeat, he is apprehended by Mermaid Man and Barnacle Boy.
Seymour's boat in the final battle is a red-colored Big Tug tugboat.
Seymour's line "And I would've gotten away with it too, if it wasn't for Mrs. Puff's meddling around!" is a reference to Scooby-Doo.
Alongside all the other sharks in Bikini Bottom, Seymour is the only one with orange hair.
The final battle is the only part where SpongeBob and Seymour have unique quotes to each other.