- Not Betty (debut)
- Ted (debut)
- SpongeBob SquarePants
- Gary the Snail
- Snail-Po mascot (debut)
- Incidental 41 (last name revealed)
- Incidental 37B
- Incidental 49
- Patrick Star
- Incidental 39 (debut)
- Squidward Tentacles
- Incidental 104
- Daydream Archie
- Daydream Incidental 42
- Daydream Fred
- Daydream Incidental 115
- Daydream Incidental 12 (cameo)
- Identity thief (debut)
- Eugene Krabs
- Old Man Jenkins (cameo)
- Two guys who threw SpongeBob in the dumpster (mentioned)
- Stingray 5000 band member (debut)
- Clams (written on CD)
- Betty (mentioned)
SpongeBob is at a diner on a dark and weary morning, while rain is pouring down outside. A patron is solving a crossword puzzle and realizes that he has lost his pen. A waitress says he can borrow hers, and does. It then shows SpongeBob sitting at a table, who says he once lost something he couldn’t live without: his identity.
He recounts the events of last Monday. In the flashback, He wakes up, and throws his blanket into the air, and says "Good morning, world, and all who inhabit it!" The blanket falls on him, and SpongeBob, being unable to see, falls off of his bed, and his alarm clock falls on top of his head. He falls down the stairs and the alarm propels him into the window. He feeds Gary and comments that he has been feeding Gary snail food for years and doesn't even know what it tastes like. He tastes it, is revolted, and his screaming of disgust is sensed at the headquarters of the company that makes the snail food. He looks at the clock and realizes that he is late for work, and quickly gets changed and skips to work. While he is skipping to work, Patrick greets SpongeBob.
After SpongeBob tells the diner people about greeting Patrick, he decides to skip to the part when he was about to serve a customer.
Later, as SpongeBob serves food to a customer, the customer tells him that he should wear a name tag so that she can thank him properly. He indicates that he is indeed wearing a name tag, but then realizes that his name tag is missing. He panics, hyperventilates, and eventually faints.
When he wakes up, he asks Squidward what happened. Squidward tells him that he fainted because he lost his name tag but assures him that his name tag is not that important, and SpongeBob hyperventilates once again until Squidward stops him saying its not the end of the world. However, just as he says this, Mr. Krabs comes out of his office and informs them that there is a uniform inspection in one hour and anyone who fails has to wear a very stinky boot all day. Squidward suggests to SpongeBob that he should retrace his steps.SpongeBob repeats everything he did that morning several times, including his "horrific incident of terror" with the alarm clock and eating the snail food. SpongeBob repeats this many times since Patrick continuously fails to say "Hi" to him. As an example, Patrick accidentally says "Hi, SpongeBoob" and laughs afterward. Still, SpongeBob fails to find his name tag. Patrick asks him if he did anything else on his way to work before noticing he lost his name tag, and SpongeBob says that he skipped merrily to Krusty Krab, said hello to Old Man Jenkins, put an apple on Mr. Krabs' desk, and was thrown into a dumpster by two thugs. Patrick suggests looking in the dumpster, and they go to search there.
During the search, SpongeBob gives Patrick two hints but he is still confused. SpongeBob does a double-take of Jack Benny while wondering, but panics that he has one minute left. Patrick finds SpongeBob's name tag on the back of his shirt, and when he alerts him to this and SpongeBob turns around, it seems to disappear and Patrick cannot remember where it was. SpongeBob gets irritated after he does this twice and soon tells Patrick to go home since he's no help. However, an annoyed Patrick says "At least I don't wear my shirt backwards!," SpongeBob sees this and realizes that he had his name tag all along, and his shirt was just on backward. At the uniform inspection, however, Mr. Krabs smells SpongeBob and is disgusted by the stench of the dumpster, and seemingly suspends him from working at the Krusty Krab.
In the end, SpongeBob finishes telling his story, and thanks to the waitress for listening, calling her "Betty." She says that her name is not Betty and that she is just borrowing someone else's uniform while hers is getting cleaned. When SpongeBob learns this, he ends the episode by doing another Jack Benny double-take.
On the storyboard featured on the Sponge for Hire DVD, they show a scene of Patrick tearfully saying, "But, I am a helper" after SpongeBob tells him to crawl back under his rock since he's no help.
|( ‣ ) Associated production music|
|( • ) Original music|
|( ◦ ) SpongeBob music|
‣ Marching to Honolulu - Kapono Beamer [title card]
‣ Eastside Story (a) - Trevor Duncan [opening]
‣ On the Beach - Kapono Beamer ["Good morning, world, and all who inhabit it."/"That was the worst thing I've ever tasted."]
‣ The Tip Top Polka/The Cliff Polka - Chelmsford Folk Band [at the Krusty Krab]
• Unknown Vibe Links - Nicolas Carr ["Thanks... uh..."]
‣ On Fire - Gregor F. Narholz [SpongeBob notices his name tag is missing]
‣ Pua Paoakalani B - Kapono Beamer, Queen Lili'uokalani [SpongeBob cries]
‣ Against the Law (c) - Wilfred William Burns [bank robbery]
‣ On Fire - Gregor F. Narholz [SpongeBob panics]
‣ The Rake Hornpipe - Robert Alexander White ["Attention, all employees!"]
‣ On Fire - Gregor F. Narholz [SpongeBob panics again]
• Idea Sting - Nicolas Carr ["Squidward, you're a genius!"]
‣ Hawaiian Happiness - Jon Jelmer [SpongeBob going back home/SpongeBob tells Patrick to say hello him again]
‣ On Fire - Gregor F. Narholz [Patrick panics]
‣ On the Beach - Kapono Beamer [SpongeBob retracing his steps]
‣ Vergnügungspark - Gerhard Trede [Patrick flubbing his lines]
‣ Ulkereien - Gerhard Trede [SpongeBob remembering what else he did that morning]
‣ Hawaiian Link (b) - Richard Myhill [SpongeBob and Patrick standing in front of the dumpster]
‣ Witty Fellow - Gerhard Trede [looking for SpongeBob's name tag in the dumpster]
• Steel Sting - Jeremy Wakefield ["Could I have another hint?"]
‣ Dramatic Cue (b) - Ronald Hanmer ["One minute?"]
• Vibe Sting - Nicolas Carr [Patrick sees SpongeBob's name tag]
• SpongeBob Closing Theme - Steve Belfer, Nicolas Carr ["Uh... I can't remember."]
‣ Marching to Honolulu - Kapono Beamer [SpongeBob's shirt is on backwards]
‣ Up She Rises - Sam Spence [uniform inspection]
‣ Eastside Story (a) - Trevor Duncan [SpongeBob finishes his story]
• Steel Sting - Jeremy Wakefield [Hawaiian sting at the end]
- This episode is available on the Sponge for Hire (with storyboard version on the special features), Complete 3rd Season, The Best 200 Episodes Ever, The Third & Fourth Seasons, First 100 Episodes, and Complete Third Season DVDs.
- "Missing Identity" was ranked #75 during the Best Day Ever event on November 9–10, 2006.
- When this episode first aired on Nickelodeon USA, it came second, while "Plankton's Army" aired first. This was due to "Plankton's Army" being heavily advertised as the episode where Plankton finally gets the Krabby Patty secret formula.
- SpongeBob sitting on the table became a popular internet meme.
- When Patrick bloops his line saying, "SpongeBoob," he then says, "Sorry people," as if a crew was filming the whole thing, subsequently breaking the fourth wall.
- The fourth wall is broken again when the waitress says, "Well, ya managed to kill eleven minutes," referencing the length of a normal SpongeBob episode.
- The title card is the same as "Reef Blower," but it is green instead.
- The name tag is somehow based on the one from "Help Wanted." Both have only SpongeBob's first name and an anchor in the middle of the background.
- SpongeBob yells "Pourquoi?" to Squidward when he was crying about losing his name tag at the Krusty Krab in this episode. "Pourquoi" means "why" in French.
- It is revealed that Nat's last name is "Peterson."
- The snail in the Snail-Po logo in this episode has a shell identical to the one of Larry the Snail. Additionally, they look very similar, though, the former does not have a unibrow.
- This is the third episode where SpongeBob tastes snail food. The first was "Opposite Day" and the second was "I Was a Teenage Gary."
- Old Man Jenkins makes a cameo appearance in this episode with his jalopy car, just like in "Sailor Mouth."
- When SpongeBob retraces his steps, he does not do the clothes changing, which is why he had to do it more times other than Patrick not saying his lines.
- At the beginning of the episode, there is a crossword. Four of the five things written are "Squid," "Chum," "Wet," "Sealweed," and "coral."
- This is the first time Zeus Cervas is credited in the opening credits.
- In two separate instances, when Patrick asks for a third clue and the waitress says that the name tag on her borrowed uniform is not hers, SpongeBob places his left arm on his right elbow with his right hand on his chin and looks at the viewers, like Jack Benny did on his 1950s TV show.
- SpongeBob's quote "The boy who cried name tag" is a pun on The Boy Who Cried Wolf.
- SpongeBob mentions the game Twenty Questions in the dumpster scene.
- The band Patrick finds in the dumpster, Stingray 5000, is a parody of the Powerman 5000.
- Snail-Po is a parody of Alpo dog food.
- The cash register is missing when Squidward brags about being a "genius."
- When SpongeBob turns around, showing his collar and name tag, the amount of filth on his shirt changes between scenes.
- When SpongeBob is worrying about where his name tag is, Squidward's animation resets for a brief moment.
- At the Krusty Krab, during the second collapse SpongeBob suffers after passing out, there is no animation of Squidward crossing his arms.
- When SpongeBob is trying to retrace his steps with Patrick, Squidward's house is not shown between SpongeBob's and Patrick's house.
- When SpongeBob is retracing his steps and it shows all of Conch Street and Patrick, there is a window on the top left corner of SpongeBob's house, where there never is.
- In the Hebrew translation, when SpongeBob tries to spell Patrick the word "name-tag," it sounds wrong since in Hebrew it is: "tagit shem" - "tag of" and "name," and he said: "name" and "tag of."
- During the split-screen of SpongeBob's attempt to retrace his steps, when he says "Bleh!" the lower right box has him slamming into the window though this happened earlier. Also, he doesn't say "Bleh!" when hitting the window, but he does when he eats Snail-Po.
- SpongeBob says "name tag" after saying "my." He also claims "name tag" is the second word, but he said three instead.
- SpongeBob waking up and saying "Good morning, world, and all who inhabit it." The blanket blinds him, making him fall off the bed, and then his foghorn clock falls onto him. He walks out of his room and trips down the stairs. His foghorn alarm sounds again, blowing him into the window. He slides toward Gary, says his "horrific incident of terror" is over, feeds Gary while singing about his meal, and decides to taste Gary's Snail-Po food, screaming "Bleah!" afterward.
- Patrick bloops his line and SpongeBob has to start all over.
- A character realizes SpongeBob's name tag is missing and starts hyperventilating.