One night, the Krusty Krab staff prepares for its 8:00 PM closing, which comes none too soon for Squidward. However, a customer walks up to the door and attempts to make an order. Squidward smugly informs him that they are closed, and the customer prepares to take his money elsewhere. Discovering the potential of late night customers, Mr. Krabs tears apart the "Closed" sign and, above Squidwards objections, proclaims the Krusty Krab to now be open 24 hours a day. SpongeBob is overjoyed at this prospect and, as the night goes on, takes pleasure in the chores he had no time to do during the day. When the time comes to take out the trash, however, he shows trepidation toward the darkness outside.
Squidward, sensing SpongeBob’s fear, weaves him a terrifying tale of the "Hash-Slinging Slasher," a clumsy Krusty Krab fry cook from years past who chopped off his own hand and replaced it with a rusty spatula. Subsequent termination of his life and his job, in that order, gives rise to the horrific specter that returns every Tuesday night to exact vengeance on all who reside in the restaurant. Squidward goes on to explain the three signs of the ghost’s return: the lights flickering on and off, the phone ringing with no one at the other end, and the arrival of the bus that had taken the fry cook's life. Squidward then laughs at SpongeBob’s shrieks of fright, but when the screaming fails to stop, Squidward assures SpongeBob that the story isn’t true. This prompts laughter from SpongeBob that also fails to cease.
By 3:00 AM, the restaurant is devoid of customers. The bored Squidward is contending with SpongeBob’s diligent cleaning when the lights suddenly begin to flicker. SpongeBob merely thinks this is another joke from Squidward, who in turn blames the electrical wiring. The next moment, the phone rings, yet remains silent when Squidward answers. Growing more nervous, Squidward tries to remember the third sign from his story. After ruling out the normal green ooze coating the walls, he and SpongeBob spy a bus pulling up to the restaurant. As the bus leaves, its lone departing passenger, a shadow-covered figure wielding a spatula, shambles toward the door.
Fearing it to be the Hash-Slinging Slasher, Squidward and SpongeBob share their final words. As the figure enters the light, however, it is revealed to be an ordinary guy, whose spatula is held in a fully-unchopped hand up his sleeve. He's arrived to apply for a job at the Krusty Krab, explaining that he tried to call ahead but hung up due to nerves. Though he and SpongeBob are relieved, Squidward notes that this turn of events does nothing to explain the flickering lights. Suddenly, the lights begin turning off and on again and everyone looks around, relieved to discover that it's only the vampire Nosferatu. Smiling at them mischievously, he flicks the lights off once more.
This episode is number 10 on Tom Kenny's Top 20. His description says:
"'Night, night, night, night.' Having Nosferatu, the vampire from the 1922 silent German Expressionist horror film appear in a Nicktoon is exactly the kind of 'what the?' moment that sets this series apart from more conventional animated shows!"
"Graveyard Shift" was ranked #64 during the Best Day Ever event on November 9–10, 2006.
This episode received a lot of controversy from parents for being frightening and creepy to the majority of younger viewers.
Being a very important fact, it should be made known that Mr. Krabs breaks the law (yet again) by forcing Squidward and SpongeBob to work 24/7; to keep the Krusty Krab open longer, he should have hired more workers, which would have been legal.
In the Russian dub, Nosferatu was renamed to Count Dracula.
The title card background is similar to the one from the episode "Rock Bottom."
In Indonesia, there were lines that had been edited:
The line "But what was that third thing?" was changed to "Who changed the colors?"
The line "How are you doing that without moving the switch?" was changed to "What are you doing with the switch?"
The line "And then, he got hit by a bus! And... at his funeral, they fired him!" was changed to "And then, he become crazy! And..after that, the fire burned him!" This one changes the Hash-Slinging Slasher's backstory completely.
Also, the line "Squidward, I use your clarinet to unclog my toilet!" was changed to "Squidward! Get rid of him!"
Near the end of the episode, the line "Nosferatu!" was changed to "Don't be naughty!"
This episode is later referenced in "Restraining SpongeBob," where Patrick uses Squidward's clarinet to unclog the toilets at the Krusty Krab like SpongeBob said he does in this episode.
SpongeBob screams 27 times and laughs 8 times.
When Squidward and SpongeBob reveal their secrets before the "Hash-Slinging Slasher" gets them, SpongeBob reveals he unclogged his toilet with Squidward's clarinet.
To "sling hash" means to work in a restaurant.
Squidward said that the Hash-Slinging Slasher comes out every Tuesday night, his ghost returns to the Krusty Krab. However, when the person who was thought to be the Hash-Slinging Slasher came to apply for a job, it was 3:00 AM, meaning that it was early Wednesday morning. Or, it was midnight when Squidward told SpongeBob, and they had the sense to remember at midnight it turned Tuesday. Or it could have been Wednesday morning because the Hash-Slinging Slasher never really arrived.
On the Box Set/DVD releases, this episode is listed as "The Graveyard Shift" instead of the normal "Graveyard Shift" name.
The word "night" is mentioned 23 times.
In the DVD Nautical Nonsense has a storyboard version and a deleted scene where SpongeBob does another thing at night he brings mail to floorboard Harry.
This is the third time a phone is seen at the cash register at the Krusty Krab. The first time was "Pizza Delivery" and the second time was "Big Pink Loser."
This episode aired on Max Schreck's 123rd birthday.
In the Polish dub, the episode's title is "Nocna zmiana" (Night Shift).
The Hash Slinging Slasher shows up at 3am. According to European Folklore, 3am is the witching hour when Witches, Ghosts and Demons are said to be active.
SpongeBob's "Night Song" has the tune of a Baseball/Hockey Charge Stadium Organ song.
The Hash-Slinging Slasher is an apparent parody of the story "The Hook" where a man has a hook instead of a hand.
The sign about the telephone ringing is a reference to the Scream.
The Krusty Krab's walls oozing green slime is most likely a reference to The Amityville Horror story. It might also reference Nickelodeon.
Nosferatu is from an old horror movie of the same name.
The Krusty Krab closes at 6:00 PM in other episodes, but in this episode, it closes at 8:00 PM.
At one scene when SpongeBob was about to walk outside to take out the trash but then stops, the night sky outside the window was normal, but in the next scene when the camera zoomed out of the glass door, the night sky was green with spooky flower clouds, then remains throughout the episode.
Before Squidward says the three signs that signal the approach of the Hash-Slinging Slasher, the wrinkles on his forehead are gone.
When Squidward tells SpongeBob "No" to "He didn't wash his hands," Squidward's eyes overlap his eyebrows.
When Squidward tries to stop SpongeBob's screaming session, his eyes are not aligned with his eyebrows.
The garbage bin outside the Krusty Krab is by the street in this episode, but it is in the back of the building in all other episodes.
When SpongeBob is mopping the ceiling, the water from the bucket does not fall to the ground.
The cash register is missing for a majority of the episode. Near the end, it returns. The only time a phone is there is when it rings, However, there is nobody there.
When Squidward says, "And he appears with the ghost of the bus," and "He opens the door, and approaches the counter!" the "Order Here" and "Galley Grub" signs are missing.
In the picture shown in the background, there is a porthole window on the window.
The Galley Grub sign reads "Gally Grub" at one point in the episode. At another point, the Order Here sign reads "Order Hear."
An "Open Forever" neon sign is seen on the Krusty Krab in one shot. However, when the "Hash Slinging Slasher" approaches the Krusty Krab, the sign is gone.
Squidward said that the Krusty Krab walls always ooze green slime. However, they never do that in all other episodes that shows the inside of the Krusty Krab.
This could be because the Krusty Krab has never been shown to be open that late at night, therefore it is not seen that they ooze green slime.
When the customers come in after Mr. Krabs says the Krusty Krab will be open for 24 hours, they are missing when Squidward goes back to the register.