Original air date: 11/11/2010
SpongeBob and Mr. Krabs need the secret formula to whip up a new batch of Krabby Patties, but Plankton is on the hunt again. To solve the problem, Mr. Krabs sends the formula on the other side of the ocean, but when it becomes apparent that they still need it, he entrusts SpongeBob with the key to go fetch it by train from the bank. But during the ride, the key goes missing, and Plankton has snuck aboard as well...
This episode contains examples of: (YMMV tropes)
- Accidental Hero: In trying to find who took the key to the secret formula, SpongeBob manages to accidentally uncover other crooks and have them arrested, such as the Jewel Triplets Gang (who stole a diamond known as Neptune's jewel of the sea) and Oran J. Roughy, a notorious embezzler.
- Always Need What You Gave Up: The main plot is triggered because Mr. Krabs and SpongeBob forgot to look at the formula to make more patties before sending it to the other side of the ocean.
- Answer Cut: Patrick randomly asks the train conductor if he's a werewolf. Suddenly a random fish turns into one.
- Bait-and-Switch: SpongeBob orders Patrick to search Plankton for the key when it goes missing, so Patrick puts on some gloves... to clean up a bowl of his. He then decides to grab a clamp... to crack open a nut as a quick snack. He then gets serious and grabs Plankton for a closer look, declaring him innocent for now.
- Big "NO!": Mr. Krabs after realizing that there is exactly enough in his bank account to pay off the damage that the train did after it smashed through the bank.
- The Butler Did It: SpongeBob accuses the train servant (who he thinks is a butler) for this reason. He didn't do it, though he did turn out to be a wanted crook.
- Call-Back: After being hit by the bus, Plankton says "Oh, now they're on time.". This might be referencing "One Coarse Meal", in which he tried to commit suicide by being run over by a bus.
- Cassandra Truth: SpongeBob initially refuses to believe Plankton when he claims he didn't take the key to the secret formula's vault, but a quick search from Patrick proves him (temporarily) innocent.
- Clueless Mystery: The key was taken by Patrick in a Noodle Incident.
- Department of Redundancy Department: When Patrick sets up a lemonade stand in an attempt to stop the train, he advertises it as "Ice cold, tasty, refreshing, and also ice-cold.".
- Didn't Think This Through: After being fed up with Plankton's theft attempts, Mr. Krabs' decides to send the Krabby Patty formula to the other side of the ocean. Unfortunately, he and SpongeBob forgot to look at it when they needed to make more krabby patties.
- Distant Reaction Shot: During Mr. Krabs' Big "NO!" upon realizing he has exactly enough in his account to pay for the damage to the bank, the camera zooms out from the bank to the exterior outside and to the entire Earth.
- Fun with Acronyms: When Spongebob and Mr.Krabs are debating whether to add land salt or sea salt in the patties. Mr.Krabs brings up the acronym SCABS for Salt Comes After Barnicle Shavings. Then he brings up the acronym LESIONS, but we never know what it means. Spongebob asks about PUSTUAL, then Mr.Krabs says "Heavens no! That's disgusting..."
- Flash Forward: The ending shows SpongeBob as an old man telling the events of the episode to his grandson, 75 years in the future.
- Halfway Plot Switch: After the mystery is cleared up, the rest of the episode is about SpongeBob and Patrick chasing, and then trying to stop, the train.
- Head Desk: Mr. Krabs' reaction when he realized that they forgot to look at the formula before they sent it to Far-Out-Ville.
- Insistent Terminology: The assistant constantly keeps reminding he is NOT a butler!
- Latex Perfection: Turns out the assistant is a crook called Orin J. Roughy, who used a mask to hide his identity.
- Noodle Incident:
- Whatever made Patrick wash SpongeBob's shorts.
- What do the acronyms LESIONS and PUSTUAL mean?
- Our Werewolves Are Different: The train conductor is asked by Patrick if he's a werewolf. Suddenly a random fish turns into one.
- Punny Name: The criminal named Orin J. Roughy ("orange roughy").
- Red Herring: All of the suspects. Although two (well, four) of them are wanted criminals, none of them stole the key.
- The Reveal: We actually get to hear some of the ingredients to the Krabby Patty secret formula for the first time: flour, barnacle shavings, turmeric, and either land or sea salt.
- "Shaggy Dog" Story: By the end of the search, it turns out Patrick took the key out of SpongeBob's shorts while he was washing them due to an "accident".
- Shout-Out:
- The title might be one to The Great Muppet Caper.
- The suspect who isn't a crook is named Miss McGuffin.
- Plankton waving a cowboy hat while riding a rocket is a reference to Dr. Strangelove.
- Title Confusion: Sometimes people get this episode mixed up with the normal episode "Patty Caper".
- Wasn't That Fun?: SpongeBob and Patrick's reaction after the out-of-control train goes through "The Twisted Tressels".
