Mister Weiner is a tall light green fish with dark spring-green fins and legs. He wears a hot dog suit, a blue and white striped shirt over the weenie suit with a light yellow undershirt, a blue bow tie, and a cardboard hat.
Mister Weiner is shown to be an expressionless, shallow person who speaks in a deadpan tone of voice and exhibits little dedication to his job. He is shown to have a weakness to SpongeBob's annoyance, and like Squidward, seems to fall victim to slapstick and abuse, as seen when SpongeBob accidentally slams the door on him and when he got hit by a bus.
He also has a criminal record, as he falsely imprisons SpongeBob by chaining him to the grill and kidnapping him against his will.
Mister Weiner is first seen at Weenie Hut, where he decides to hire SpongeBob. However, he is disgusted at SpongeBob's Weenie Patties and fires him on the spot.
Later in the episode, Mister Weiner has his thugs kidnap SpongeBob from his home and forces him to cook more Weenie Patties due to his customers' fondness for them. However, SpongeBob's past employers try to take him back as well, due to the popularity of his food, but Mister Weiner and the other employers are defeated by the Killer Krabby Patty. He is subsequently hit by a bus.
At the end of the episode, he is shown eating at the Krusty Krab along with the other restaurant owners.
Mister Weiner is the first person to employ SpongeBob and the first to kidnap him in the episode.
Although the end credits spell his name as "Weiner," the proper German spelling is actually "wiener."