- Squidward Tentacles
- Squidward's bonsai (debut; cameo)
- SpongeBob SquarePants
- Patrick Star
- Flying Dutchman (debut; cameo)
- Fish in magazine
- Sandy Cheeks (cameo)
- Eugene H. Krabs
- Clay (cameo)
- Jennifer Millie (cameo)
- Jimmy Gus (cameo)
- Nancy Suzy Fish
- Tina Fran
- Seagulls (debut)
Squidward is proud of having just finished his wax sculpture of himself and declares he has "conquered all artistic medium." But then, he is annoyed by SpongeBob and Patrick, who are playing a loud game. When Squidward goes to take a bath, SpongeBob and Patrick begin to toss around a shell as a Frisbee, but it flies into Squidward's house and hits the wax sculpture. SpongeBob and Patrick think they've injured Squidward, and after several humorous attempts to "resuscitate" him, they believe that Squidward has died.
Squidward, fresh from his pampered bath, dramatically emerges in a rush of steam from the warm bathroom, wearing talcum powder and a white bathrobe and towel. SpongeBob and Patrick believe they are seeing Squidward's "ghost" and, hoping to avoid any haunting or punishments, place themselves as Squidward's willing servants. Squidward, instead of telling them he's not dead, gleefully plays along in order to have them serve and pamper him, do chores, and simply entertain him.
Eventually, SpongeBob and Patrick are instructed to clean out one of Squidward's "messy" rooms. Upon cleaning, they come across a comic book inspired by the story of the Flying Dutchman (who haunted the seas because his body was used as a window display in a clothing store and was never put to rest), and decide that since Squidward is a vengeful spirit, and they have to put Squidward to rest. SpongeBob and Patrick try to get Squidward to go into a casket, but he refuses. SpongeBob and Patrick then try to give him a proper burial as well as a funeral.
Squidward eventually admits his charade, but SpongeBob and Patrick believe that Squidward is simply in denial about his death. SpongeBob blows a giant bubble that engulfs Squidward and sends him floating up to "the great beyond" truly sending him out of the water and high in the air with a flock of seagulls, much to Squidward's discomfort.
|( ‣ ) Associated production music|
|( • ) Original music|
|( ◦ ) SpongeBob music|
‣ Smoke and Dreams - Otto Sieben [opening]
‣ Hilo March - The Hawaiian Serenaders [SpongeBob and Patrick play games.]
‣ Bossa Cubana - Gerhard Narholz [Squidward takes a bath.]
‣ Gator - Steve Belfer [SpongeBob and Patrick are tossing a shell back and forth.]
‣ Bossa Cubana - Gerhard Narholz [Squidward hears a thump.]
‣ Gator - Steve Belfer [SpongeBob and Patrick enters Squidward's house.]
‣ Lovely Scenery (c) - Mladen Franko ["SQUIDWARD! AHHHHHHHHHHHH!"]
‣ Bossa Cubana - Gerhard Narholz [Squidward puts on a towel.]
‣ Dangerous (a) - Mladen Franko [SpongeBob and Patrick attempt to put the statue back together.]
‣ Dramatic Cue (h) - Ronald Hanmer [The sculpture's eyes turn over.]
‣ Deep Grief 1 - Otto Sieben ["He's pushing up daisies!"]
‣ Tales from the Swamp (a) - Ron Goodwin [Squidward comes out of the bathroom.]
‣ Dramatic Cue (d) - Ronald Hanmer ["Look what you've done to me!"]
‣ In the Crypt - Dave Hewson ["Enough! Listen up!"]
‣ Tales from the Swamp (c) - Ron Goodwin [The end of Squidward's speech]
‣ Seaweed - Steve Belfer [SpongeBob and Patrick take Squidward outside.]
‣ The Rake Hornpipe - Robert Alexander White [SpongeBob and Patrick feed Squidward.]
‣ Stack of Leis - Kapono Beamer [Night passes.]
‣ In the Crypt - Dave Hewson ["What's this? Napping on the job?"]
‣ The Achterhoek Dances - Jan Rap [SpongeBob and Patrick clean the back room.]
‣ In the Cradle (b) - Dick Stephen Walter [SpongeBob and Patrick find a comic book about the Flying Dutchman.]
‣ Gator - Steve Belfer [SpongeBob and Patrick put Squidward to rest.]
‣ Funeral Music - Alfred Kluten [The mourners]
‣ Hawaiian Happiness - Jon Jelmer [Squidward confesses.]
‣ Vibe Link (b) - Richard Myhill ["Patrick, say that again."]
‣ Queen's Aloha Oe C - Kapono Beamer, Queen Lili'uokalani [The ending]
- This episode is available on the Halloween, Complete 1st Season, First 100 Episodes, and Karate Choppers DVDs.
- "Squidward the Unfriendly Ghost" was ranked #95 during the Best Day Ever event on November 9–10, 2006.
- This episode marks the debut of the Flying Dutchman, although, he is only seen in pictures and does not physically appear. His first live appearance is in the episode "Scaredy Pants."
- This is one of the seven episodes in which the 1986 Paramount logo is plastered with the 2002 Paramount logo. The others are "Help Wanted," "Squeaky Boots," "F.U.N.," "Employee of the Month," "Karate Choppers," and "Rock Bottom."
- This episode premiered in Canada on September 16, 2000.
- When SpongeBob says "G7," the chord is played on a ukulele.
- When SpongeBob and Patrick attempt to revive the sculpted replica of Squidward that they believe is him, Patrick says he knows what to do and attempts to give him CPR. Patrick also uses CPR to revive Squidward after he falls unconscious from choking in the episode "Naughty Nautical Neighbors."
- On the October 22, 2015 airing, this episode was paired up with "Ghost Host."
- This episode premiered on Mark Hamill's 48th birthday.
- In the French Dub, this episode is called "Le Fantôme de Carlo," which translates to "The Ghost of Squidward."
- The episode is briefly featured in the 2019 film Pet Sematary where the scene used in the film is during when Squidward gets out of the shower and finds his wax sculpture deformed. Interestingly, Clancy Brown, who in general voiced Mr. Krabs and has a cameo in this episode, had previously acted in Pet Sematary Two as the sheriff of Ludlow and an abusive stepfather named Gus Gilbert, who gets killed by his stepson's reanimated dog he killed and then reanimated as a murderous zombie.
- The episode title is a parody of Casper the Friendly Ghost.
- During the scene when Patrick and SpongeBob are carrying Squidward around in servitude to him, with Squidward complaining it is "too hot" or "too wet," they stumble onto an aquatic version of the painting La Troupe de Mlle. Eglantine. Squidward quips that it is "Too loose, Lautrec," a pun on the name of the painting's artist, Henri de Toulouse-Lautrec, with an accompanying rim shot.
- The painting is also named Troupe de Poisson, play on the painting La Troupe de Mlle.
- Right before wax Squidward frowns again, a bit of his head randomly disappears for a second.
- When Squidward is on the royal bed, SpongeBob's house is missing.
- When SpongeBob and Patrick enter Squidward's house to retrieve the shell, they exit from the lift to Squidward's room. Additionally, Squidward's door has a different appearance. In other episodes, the appearance of his door is different from how it is depicted in this episode.
- When SpongeBob says "Nevermind," his eyelashes are missing.
- Before Squidward goes to check if SpongeBob had played music for him, the latter's arms are at the bottom of his pants. However, when Squidward says, "You're supposed to be making music for me," his arms are on the sides.
- When Mr. Krabs says, "We all came when we were sure you were dead," his white undershirt is gone. It then returns again.
- When Squidward says, "Now get rid of that tombstone and tell all your friends to go home!" to SpongeBob, the mourners go home, but the tombstone remains.
- When SpongeBob is running to the green coral, the shell is never seen lying near the coral.
- When Squidward shouts, "Hey," a small white bubble is seen for a split second on the left side of the screen.
- The rock SpongeBob throws does not appear to be broken after he and Patrick try to figure out what to do next.
- When Patrick is blown around the room, it shows that he lands vertically across the face, while the next still frame indicates he landed on his face horizontally.
- When the camera pans down to reveal that the Squidward sculpture has melted, SpongeBob and Patrick are standing next to each other. However, in the next shot, SpongeBob and Patrick are standing across from each other.