Squilliam Fancyson III is Squidward's arch-rival whom that he met in high school band class. He appears in the episodes Band Geeks, Squilliam Returns, House Fancy, Professor Squidward, I Heart Dancing, Keep Bikini Bottom Beautiful, and Back to the Past. He is a very wealthy, snooty, unibrow-endowed octopus who has succeeded in everything Squidward has failed in and thus looks down upon him. Squidward is painfully jealous and constantly attempts to show Squilliam he's not a loser, with varying results. Like other squid/octopus characters, Squilliam's character model is nearly identical to Squidward, but he has a unibrow and he wears a fancy maroon robe. He owns a private yacht, a private lake, a private heliport, a private island, and a balloon/casino. He owns a fancy house which made an appearance in the TV show House Fancy. Squilliam is played by Dee Bradley Baker.
Squilliam's first appearance was in "Band Geeks", where he challenged Squidward to play his band at the Bubble Bowl, as his own band could not make it. However, at the end of the episode, Squilliam arrives at the Bubble Bowl anyway to watch Squidward fail (which may imply that he was just setting up Squidward to make a fool of himself), but upon seeing the band's surprisingly good performance, Squilliam appears to have a heart attack and is rushed to the hospital on a stretcher.
Squilliam returns in the aptly named episode "Squilliam Returns", where Squidward tells him that he is the owner of a five-star restaurant in an attempt to show him up. Although Squilliam is initially impressed by SpongeBob's new found fine dining expertise, Squidward is ultimately humiliated when SpongeBob cannot remember his own name and goes insane and destroys the restaurant.
In "House Fancy", Squilliam's ridiculously luxurious house is featured on the TV show of the same name. The house features, among other things, a golden toilet, an elevator with a built-in hot tub, and a massive sculpture of his unibrow made entirely out of gilded doorknobs. Squidward's jealousy once again gets the better of him when he calls the show's host, Nicholas Whithers, claiming that his house is better than Squilliam's. Although Squidward's house is destroyed as a result of his attempts to make it fancier, Whithers sees his destroyed house as a work of art and proclaims it to be better than Squilliam's. Squilliam breaks down and falls over, in tears, as he is once again upstaged by Squidward.
In "Professor Squidward", he is shown to teach music at Bikini Bottom University. When Squilliam is absent, Squidward claims to be him so that he can teach the class himself. Squilliam also appears at the end of "I Heart Dancing", where, after Squidward is given the part of a line dancer for Squilliam, he begins to abusively train him in the same manner that Squidward did to SpongeBob. In "‘‘Back to the Past", he is seen putting up a sign in Bikini Bottom when Man Ray took over.
Squilliam is rich and fancy. He acts more mature than Squidward, but makes no secret of the fact that he considers himself superior to others due to his enormous wealth. He is a mean, selfish, and arrogant octopus who takes great pleasure in asserting his perceived superiority over middle-class citizens like his arch-rival Squidward. He also speaks in a very mocking tone, placing great emphasis on his low regard for Squidward and an equally large amount of inflated praise in his lavish lifestyle. Despite his selfish personality, he somehow makes friends easily (probably for letting people in his private jet, yacht, airship/casino, etc.).
Like Squidward, Squilliam is a narcissist. He considers himself to be undeniably handsome.
Due to the fact that he looks similar to Squidward, some fans have it rumored that Squilliam is, in fact, a showoff.
Squilliam is seen to like having SpongeBob around. The most likely reason for this is because SpongeBob's antics usually end up making Squidward look bad, even though he doesn't mean to do that. SpongeBob shows respect for Squilliam as well. The two have a good friendship and have never had any arguments in the series.
Squilliam is rarely seen with Patrick on the show, but when they are seen together on the show, they appear to have a good friendship and have never had any arguments in the series.
Squilliam is a small octopus with six tentacles (which is similar to Squidward). He wears a red and black robe and has an ascot. Squilliam has a large black single eyebrow, or unibrow. He has had it in every episode. In "Band Geeks", he shows pride in it when he calls it "big and valuable". In "Professor Squidward", this feature is how the police told him apart from Squidward Tentacles. In the episode House Fancy, Squilliam had a large replica of his unibrow that was made of 500 solid gold painted doorknobs.
"Sounds as though you've got a dying animal to attend to, eh old chum?"
"I'm filthy stinkin' rich!"
"It's a gilded doorknob."
"Come on everyone; let's go take a ride in my balloon slash casino!"
Squidward: "Oh no, he's hot!"
(referring to his unibrow) "It's big and valuable. I'm a leader of a big fancy band right now. And we're supposed to play the Bubble Bowl next week."
"Squidward Tentacles has the fanciest restaurant in Bikini Bottom, and he does not suck eggs (After Squidward tricks him into thinking he actually does own a 5-star restaurant)."
"Explain what? That you, Squidward Tentacles, voted most likely to suck eggs in high school, (walks into Krusty Krab) are trying to pass off a lousy burger stand as a five-star... (Gulps) ...restaurant!?"
He has some similarities as Squidward, but more different: He's an octopus as Squidward, his house is dark blue and the bottom floor looks identical to Squidward's but it has multiple stories, he has different clothes, and so on.
Squilliam's voice sounds slightly similar to actor Paul Lynde's.