when did spongebob start working at the krusty krab
After he fulfils the task given by Mr. Krabs.
Help Wanted (SpongeBob SquarePants)
However, he is tasked to find a seemingly rare high-caliber spatula because the owner, Mr. Krabs, considers him unqualified for the position. Eventually, crowds of ravenous anchovies stop by the Krusty Krab and demand meals. SpongeBob returns from his errand, having fulfilled the request of Mr. Krabs and found a mechanical spatula. He utilizes the spatula to satisfy the anchovies' hunger. SpongeBob is then welcomed by Mr. Krabs as a Krusty Krab employee against the wishes of Squidward, the cashier of the Krusty Krab.
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Help Wanted (SpongeBob SquarePants) [SEP] Introduction
Hillenburg gave up the idea, and started new with the idea he and Derek Drymon came up for "Help Wanted" based on an experience Hillenburg had in the Boy Scouts. The original idea would be used for the later episode "Pizza Delivery". The episode was written by Hillenburg who also functioned as storyboard director as well as storyboard artist, Derek Drymon, who also functioned as the credited storyboard artist, and Tim Hill. The animation was directed by the show's supervising director, Alan Smart. "Help Wanted" features a posthumous musical performance from Tiny Tim singing his song "Livin' in the Sunlight, Lovin' in the Moonlight".