%% SEEN IT BEFORE?: If it happens in different episodes to the same character, you could put the trope in that character's description on the Characters page.
[[quoteright:350:[[DeathGlare http://static.tvtropes.org/pmwiki/pub/images/PinkiePieDeathGlare_1210.JPG]]]]
[[caption-width-right:350:[[GenkiGirl Pinkie Pie]] [[OOCIsSeriousBusiness isn't quite]] [[NotHimself herself today]]. (Creator/AndreaLibman ''really'' earned her pay that week.)]]

->'''Pinkie Pie:''' Sure, Rainbow Dash and Fluttershy had to house-sit for that vacationing bear, but what are the chances all my other friends would have plans this afternoon, too?

-> Written by Meghan [=McCarthy=]

Pinkie Pie holds a birthday party for her pet alligator, Gummy, inviting all her friends. Afterwards, all the guests compliment Pinkie on the great party, with Twilight saying "We should do this again soon!". Pinkie, being Pinkie, interprets this a little ''too'' literally...

The very next day, Pinkie shows up at each of her friends' houses, eagerly offering invitations to Gummy's "''after''-birthday party" that afternoon. Her friends, however, aren't as enthusiastic...

->'''Twilight/Applejack/Rarity:''' ''This'' afternoon? As in, ''"this afternoon"'' this afternoon?

(Fluttershy and Rainbow Dash don't get a chance to say this, as Pinkie Pie finishes their statement for them.)

All of them offer excuses for why they can't come, but it isn't until Pinkie gives herself time to think about it that she realizes this.

Once she notices Twilight picking up a package from Sugarcube Corner (instead of studying, like she said she would be), Pinkie decides to investigate. After sneaking around Ponyville in disguise, overhearing several secret conversations between her friends, angrily chasing Rainbow Dash around town, and a tense exchange with Applejack, Pinkie suspects that her friends don't like her or her parties anymore. To get some confirmation on her suspicions, she interrogates Spike into giving her information, even bribing him with a bowl of gems, but gets frustrated when he doesn't know what she's talking about.

->'''Spike:''' What do you wanna hear?! Tell me what you want me to say and I'll say it!\\
'''Pinkie Pie:''' ''Tell me'' that my friends are all lying to me and avoiding me because they don't like my parties and ''THEY DON'T WANT TO BE MY FRIENDS ANYMORE!''\\
'''[[LiteralMinded Spike]]:''' [[ExactWords "Your friends are all lying to you and avoiding you because they don't like your parties and they don't want to be your friends anymore."]]

Pinkie is satisfied at seemingly having her suspicions confirmed, but immediately feels depressed and lonely upon thinking she's lost her friends, to the point where her poofy hair deflates and her color scheme becomes muted and dull.

In her mentally unhinged state, Pinkie ends up holding a morose and disturbing second party with several inanimate objects as her new "friends". Rainbow Dash stops by, apologizing for her behavior earlier, and offers to take Pinkie to Sweet Apple Acres. Pinkie repeatedly refuses to go, leaving Rainbow Dash no choice but to forcefully drag her there. Upon arriving at the farm, Rainbow leads Pinkie to the barn, where a surprise party is being held with all their friends. Pinkie assumes this is a surprise ''farewell'' party to celebrate her being booted from the group, until everyone explains that it's her own surprise ''birthday'' party. Pinkie, realizing she'd forgotten it was her own birthday, returns to her old cheery self and decides to enjoy the party. Twilight writes to Princess Celestia from the party, stating the [[AnAesop Aesop]] that one shouldn't expect the worst from their friends.


* AgelessBirthdayEpisode: Pinkie's and the first one in the series.
* AnimateInanimateObject: When Pinkie is going crazy, she has a brief delusion where her pretend friends all move and talk on their own, without any puppetry assistance.
* AssKicksYou:
** When dancing during Gummy's birthday party, Pinkie Pie knocks both Twilight and Fluttershy into a wall with some overly enthusiastic moves of her rear half.
** When Rainbow Dash attempts to get Pinkie Pie to come with her, Pinkie Pie bucks forward and then sits on her head. Pinkie Pie is also drawn significantly heavier than Rainbow Dash.
* BadLiar: All the main cast save maybe Twilight Sparkle show this tendency coming up with excuses to avoid Pinkie...especially Applejack, [[FridgeBrilliance since she's the Element of Honesty]].
* BirthdayEpisode: Pinkie Pie's, though it's not evident until the end.
* BlackComedyBurst: Pinkie Pie's breakdown... one of the darkest scenes in the series... is PlayedForLaughs.
* BlatantLies:
** How her friends get out of going to Pinkie's after-party, and then how they cover up their own goings-on.
** Rainbow Dash '''draws''' a wristwatch on her hoof, right in front of Pinkie, and then points out "Look at the time!" to try to get her and Fluttershy away from Pinkie.
** At one point Applejack says that Pinkie can't come into her barn because they're renovating it and there's too much construction going on. The other ponies back her up by making [[SayingSoundEffectsOutLoud blatantly fake tool noises]].
* {{Bowdlerise}}: When the episode airs on Treehouse TV in Canada, all instances of the word "loser" are silenced.
-->'''"Rocky:"''' Not so bad? Puh-leeze! They're a bunch of "losers"!\\
'''Pinkie Pie:''' Oh, come on now. "Loser" might be a little strong, don't you think?\\
'''"Sir Lintsalot:"''' After the way they treated you, I'd say "loser" isn't strong enough!
* BrickJoke: Written invitations.
* CarnivoreConfusion: Best summed up by one [=YouTube=] comment ([[DontExplainTheJoke Madame Le Flour is a flour sack, by the way]]):
-->'''[=ChunkeeNoodleSoup=]:''' Madame Le Flour is eating cake. Does anyone see what's wrong with this?
* ComedicSociopathy: Spike is oblivious to Pinkie's angst during and after the interrogation, even though it should be perfectly obvious to any observer, and this ends up making things worse. Granted, he's got a pretty bad record of reading people from before too (not noticing that the audience hated Pinkie Pie's performance in "Over a Barrel" and Rarity's fashion show in "Suited for Success", thinking his crush on Rarity is a secret in "Green Is not Your Color", almost all of "Owl's Well That Ends Well"...), but this is the most extreme example, with him only being interested in the "nice spread" -- a huge bowl of gems -- and saying whatever it takes to get his claws on it.
* ComicallyMissingThePoint:
** After hearing her friends' increasingly BlatantLies about why they can't come to the after-party, Pinkie somehow finds Rainbow Dash and Fluttershy's absurdly convoluted StereoFibbing the only one that seems plausible.
** Spike has no clue about what he's being interrogated for or about, nor does he get one at any point. Ironically, this means he ends up frustrating Pinkie Pie with the same kind of literal-minded, cluelessly irrelevant answers you'd expect from her in a similar situation.
* CompanionCube: Pinkie's "new friends". A pile of rocks, a dust bunny, a bag of flour, and a pail of turnips.
* ContinuityNod: Pinkie's hair goes back to [[{{Recap/MyLittlePonyFriendshipIsMagicS1E23TheCutieMarkChronicles}} the state it was before she discovered how to smile.]]
* CreepyCircusMusic: Accompanies Pinkie Pie during her SanitySlippage, complete with cacophonous trumpet stings when she [[TwitchyEye twitches.]]
* DarkReprise: A physical variant. Pinkie following and doing StealthHiBye to Rainbow Dash to go on a pranking spree in "Griffon the Brush-Off"? Hilarious. Pinkie following Rainbow Dash demanding to know why she's been avoiding her all day? Disturbing and creepy.
* DeathGlare: Pinkie gives one to Applejack. It's scary enough to rival Fluttershy's.
* DiscreetDrinkDisposal: After the SpitTake, Rarity politely continues drinking, but once Pinkie's back is turned she discreetly spits her mouthful of punch into a potted plant.
* DoubleTake: Rainbow Dash first casually says "Hi, Pinkie Pie" to a disguised Pinkie, before freezing on the spot with her mane and tail hair completely straight.
* DramaticSpotlight: Parodied. Pinkie Pie draws the (wrong) conclusion that her friends have all turned against her from her interrogation of Spike, and declares so in a Dramatic Spotlight. Then it turns out the light comes from the lamp she used to interrogate him with, as he turns it off.
* {{The Easy Way Or The Hard Way}}: After Pinkie Pie refuses to follow Rainbow to Sweet Apple Acres, Rainbow filally lets her frustration get to her.
--> '''Rainbow Dash''': Oh, you want to do this the hard way? We're doing this the hard way!
** The "hard way" turns out to be dragging Pinkie there by the tail.
* EtTuBrute: PlayedForLaughs when Pinkie Pie thinks that her friends don't like her parties anymore, only to realize that her friends are setting up a birthday party for her.
* ExactWords: Spike tells Pinkie exactly what she told him to say in order to get the bowl of gems she was bribing him with.
* ExpositoryHairstyleChange: Pinkie's depression and SanitySlippage is demonstrated by her normally wildly curly mane going very straight, [[CallBack just like in "Cutie Mark Chronicles"]] when we see her dour upbringing before she learned to smile. When she snaps out of it at the end, [[HairReboot her mane returns to normal]].
* FailedASpotCheck: For some reason, Twilight Sparkle fails to notice a highly-obvious TinCanTelephone dangled just inches above her head until she's on her way out of Sugar Cube Corner.
* FalseConfession: Spike repeats Pinkie's exact phrasing so he can get the gems she's bribing him with, and is oblivious to her SanitySlippage.
* {{Fauxshadow}}: Most of what happens at Gummy's birthday party... except for Pinkie saying "I can't tell you that, silly; then it wouldn't be a surprise!"
* FelonyMisdemeanor: Spike "confesses" (with much dismay and shame) to spilling juice on one of Twilight's books, using up all the hot water, and doing muscle-man poses in front of a mirror when no-one is watching.
* ForgottenBirthday: Inverted. It's only at the end that Pinkie realizes it's ''her own'' birthday, and the others had made plans to throw her a surprise party well in advance.
* FunnyBackgroundEvent:
** Gummy can be seen rolling around on a ball of string at one point while Pinkie is talking.
** When the Mane Six start dancing at the end, Spike does some [[GratuitousDiscoSequence disco dancing]] in the background.
* FunnySchizophrenia: Pinkie Pie talking to her imaginary friends during her SanitySlippage.
* GettingCrapPastTheRadar: [[https://derpicdn.net/img/view/2012/9/4/89898__safe_animated_spike_dancing_party+of+one.gif Spike's dancing]] during the ending party is [[GratuitousDiscoSequence very suggestive]].
* GotMeDoingIt: Rainbow Dash briefly talks back to "Rocky" as if she's actually mad at "him", before she realizes what she is doing.
-->'''"Rocky":''' You heard th' lady! She ain't goin' nowhere, chump!\\
'''Rainbow Dash:''' Who're you callin' a chump, ''chump''?! (''{{beat}}'') Ugh... That's it: party's over.
* HiddenDepths: You wouldn't have believed that an episode of ''My Little Pony'' starring the silly party-crazy member could be so profound... [[SurrealHumor and creepy]].
* IHaveToWashMyHair: Rarity's excuse. She even ''sinks her mane into garbage'' to make it plausible.
* IncrediblyObviousBug: Pinkie dangles a [[TinCanYouHearMeNow can-onna-string]] just above Twilight Sparkle's head, almost in front of her face, to listen in on her conversation with Mrs. Cake. Locating the listening device [[AmusingInjuries proves ill]] for Twilight.
* INeedToGoIronMyDog: Fluttershy and Rainbow Dash's excuses involve housesitting for a bear that's vacationing on the beach to gather sea shells or swim or something.
* InnocentlyInsensitive: Spike is more concerned with the plate of jewels than how Pinkie's feeling. He's just managed to convince her that she's lost all her friends and no-one likes her parties. She appears ready to burst into tears; Spike's happily munching minerals.
* InterrogatedForNothing: Spike honestly has no idea what Pinkie wants to know during his interrogation, so simply tells her what she wants to hear. Ironically, he might have known or guessed about the surprise party, so if she'd merely asked him what her friends were doing that afternoon, he might have been able to tell her, and avoid all of the [[EnhancedInterrogationTechniques unpleasantness]].
* IronicEcho: There are two occasions when Pinkie Pie is staring at Applejack and then stops after saying "Okey-dokey-lokey." The first time she says it happily and it signals a relief of the tension. The second, not so much.
* KubrickStare: Along with [[WideEyesAndShrunkenIrises slowly shrinking irises]], this is Pinkie Pie's expression.
* LettingTheAirOutOfTheBand: Twilight rings the counter bell at Sugercube Corner while happy, carefree music plays. Then Twilight reminds both the music and Mrs. Cake that this pick-up is serious business.
* LiteralMinded:
-->'''Pinkie:''' Oh, Twilight, you shouldn't ''hit'' the books. You should really just read them.\\
'''Twilight:''' I'll keep that in mind!
* LockedOutOfTheLoop: Pinkie doesn't realize that the reason her friends are avoiding her is because they're planning her own birthday party until the very end.
* LoudGulp: Applejack does this (twice) while Pinkie is glaring at her just after she'd fed her some fibs (as usual, not very convincingly, Applejack being a well-known BadLiar).
* MessyHair: Upon waking up, Twilight has strands of hair going all over the place.
* MickeyMousing: During Pinkie Pie's SanitySlippage, a trumpet glissando plays every time she twitches.
* MinimalistCast: Only the Mane 6, Gummy, Spike and Mrs. Cake show up in this episode, with the last two only in one scene each. The first shot is the only time that background ponies appear.
* MoodWhiplash: When Pinkie realizes the party her friends are throwing for her is her own birthday party, she immediately reverts to her usual happy, cheerful self.
* NiceHat: In-universe, anyway; Pinkie's invitation basket hat.
-->'''Rarity:''' Love the new hat. Very modern. What's the occasion?
* NiceJobBreakingItHero: If Spike had told Pinkie Pie pretty much anything else, then we probably wouldn't have seen Pinkie Pie suffer SanitySlippage. To be fair though, he had no idea what she was going on about and her prodding didn't help things.
* NonVoyageParty: Pinkie recognizes that her friends are acting suspicious and making excuses for why they can't attend her spontaneous party for Gummy. She tries to coerce Spike into telling her why, and demands he tell her the truth as she has come to believe it: they don't like her parties and want to kick her out of the group. She is despondent and suffers SanitySlippage until Twilight makes a point she can't dismiss:
--> '''Twilight Sparkle:''' If this is a going away party, then why does the cake I picked up from Sugar Cube Corner say "Happy Birthday Pinkie Pie"?
* OffscreenTeleportation: During Gummy's party, we see Twilight at the punch table but in the next scene, she's dancing with Fluttershy.
* OnePersonBirthdayParty: Pinkie celebrates a party with a bunch of inanimate objects because her friends were busy, and she thinks that they don't want to be her friends anymore. However, she had forgotten that day was her birthday, only remembering upon Rainbow Dash forcing her to go to her surprise party.
* OOCIsSeriousBusiness: When Pinkie's not happy, she's ''scary''. The eponymous "party of one" isn't like Pinkie's usual parties. Instead of a childlike birthday party, it's more like an adult formal dinner party. She also drops her quirky vocabulary and starts to use a more serious tone and more formal words, even using snooty accents for her "guests". Finally, her attitude towards her "new friends" is somewhat distant.
* PaperThinDisguise: [[InvertedTrope Inverted]]. Pinkie's sneaking disguise is anything but paper-thin, using wacky glasses, a hay bale, a trenchcoat, and a beanie, but Rainbow Dash is still able to recognize her instantly, without even reacting as if it's odd. Pinkie's probably [[WeirdnessCoupon the only one]] who would ever use that disguise. And Pinkie's behavior is so random most of the time, her friends have pretty much come to expect this of her.
* PerpSweating: Pinkie Pie does this to Spike in an attempt to find out why her friends are avoiding her.
* PlotDrivingSecret: The party for Pinkie Pie. It goes about as well as every other cartoon that's done it.
* PoseOfSupplication: Pinkie, after Spike tells (or rather, repeats back to) her that her friends are avoiding her because they don't like her parties.
* PrehensileTail: Rarity is able to carry a full sheet cake in her tail curls.
* PsychologicalHorror: Pinkie's breaking from her perceived loneliness is absolutely ''creepy''.
* {{Pun}}:
-->'''Pinkie Pie:''' Who's ready to shake their hoove thang?
* ReactionShot: During Pinkie's "Singing Telegram" song, we get a lot of these from the other Mane Six. The funniest would have to be Twilight's, whose expression can only be described as concern.
* ReflectiveEyes: A reflection of Applejack can be seen in Pinkie's eyes twice in the episode, when Pinkie tries to stare her down and later want to see what's inside the barn.
* SanitySlippage: Who would have thought a pink GenkiGirl could be downright scary?
* SayingSoundEffectsOutLoud: When Applejack claims that there's lots of construction going on in the barn, Rainbow Dash stage-whispers, "You heard her! Construction!" Cue a lot of ponies attempting to vocalize the sounds of power tools, including Rainbow Dash saying "Drill, drill!" as well as Twilight saying [[UnsoundEffect "Safety gear!"]]
* ScrewThisImOuttaHere: During his after-birthday party, Gummy turns away when he sees Pinkie Pie's inanimate guests. In the next shot of the whole table, he's gone. Though it's unclear whether he went off to do his own thing or [[OOCIsSeriousBusiness even]] ''[[OOCIsSeriousBusiness he's]]'' [[OOCIsSeriousBusiness unnerved]] by Pinkie's SanitySlippage.
* ShoutOut:
** The episode title could be referring to ''Theatre/DinnerForOne'', which also includes a scene with someone walking around a table and faking the voices of the absent guests.
** The pile of rocks is called "Franchise/{{Rocky}}", and Pinkie Pie voices him in the manner of a Creator/SylvesterStallone impression.
** Pinkie Pie [[OffscreenTeleportation playing]] an angry [[WesternAnimation/NorthwestHoundedPolice pick-a-boo]] on Rainbow.
** The ScareChord from ''Franchise/{{Predator}}'' plays when Pinkie does her OffScreenTeleportation when she's interrogating AJ.
** Spike [[Film/TheGoonies confessing bad things he did]] when Pinkie Pie interrogates him.
** Pinkie Pie does [[Film/{{Clue}} a singing telegram]].
* SpitTake: Rarity does one right at Pinkie Pie's face when seeing Gummy in the punch bowl; she doesn't seem to notice and/or care.
* StepfordSmiler: When Pinkie Pie's smiles are fake, you know something is very, very wrong.
* StealthHiBye: Pinkie, trying to find out why she's ignoring her, is continually one step ahead of Rainbow Dash's hiding places before she ducks into Applejack's barn.
* StealthPun: Gummy sneezes for no apparent reason after popping out of the top of the bale of hay Pinkie is wearing. Presumably, it's a case of ''hayfever''.
* StereoFibbing: Even Rainbow Dash's and Fluttershy's ''body language'' reflects their StereoFibbing. Whoever says "Playing beach volleyball!" waves her front hooves above her head, while whoever says "Collecting seashells!" waggles them up and down at chest level. When their stories mutate into "Collecting volleyballs!" and "Playing seashells!", each pony waves one hoof above her head ''and'' waggles the other up and down by her side.
* SuperSpeed: Pinkie Pie shows once again she can keep up with Rainbow Dash without trouble, leaving a pink streak behind her.
* SurpriseParty: Rainbow Dash and the others throw this for Pinkie.
* TalkingToThemself: Pinkie initially tries to defend her friends from the barbs of the second party's guests, especially Rocky and Sir Lintsalot. Which are voiced by Pinkie herself.
* ThatPoorPlant: At Gummy's birthday party, Rarity spits her punch into a plant after finding out Gummy has been swimming in it.
* TheReasonYouSuckSpeech: Pinkie gives one to her friends when she accuses them for lying to her and setting up a farewell party which is really her own birthday.
* TinCanTelephone: How Pinkie tries to listen on Twilight and Mrs. Cake's conversation. Hilariously, she seems to be trying to peer at it too. Through the string.
* TwoScenesOneDialogue: Pinkie is delivering her singing telegram to each of her friends, and the scene cuts from one to the next with each line. By the time she gets to Fluttershy, she's completely tired out.
* UnwittingInstigatorOfDoom: It's no thanks to Spike's SarcasticConfession that Pinkie Pie goes crazy.
* WhamLine: "If this is a farewell party, why does the cake I picked up from Sugarcube Corner say "Happy Birthday, Pinkie Pie"?"
* YouDoNotWantToKnow: Rainbow Dash says this to Twilight after the unicorn asks about a reference to Pinkie's previous "party".