He first appears in the episode saying that SpongeBob and Patrick are not allowed in Tentacle Acres. Since SpongeBob and Patrick do not leave, he asks his colleague, Orville, if he has his nightstick ready. The two are then knocked out by Patrick's fried oyster skin breath that had gone through the speaker.
Although unlikely, the gatekeeper may have appeared chasing Squidward as the end of the episode.
He is one, if not the only, gatekeeper that works for Tentacle Acres. He might also be a guard.