Annie is puttying together a Dia de Los Muertos party to earn extra credit. To ensure her party is a success she needs everyone in the study group to attend. This however conflicts with Jeff's attempts to get together with his statistics professor. Jeff eventually promises to attend the party, but only after his advances are turned down.
At Annie's party, events spin out of control: Jeff leaves with Chang to try again with Slater; Pierce suffers side effects from the drugs Star-burns gave him; and Shirley projects her feelings about her failed marriage onto Britta's misgivings over Jeff and Slater.
The Community episode "Introduction to Statistics" contains examples of:
- Acquired Poison Immunity: Jeff invokes this as the reason Annie's crying would no longer work on him. It does not work
- Becoming the Costume: Abed
Abed: I am Batman.
- Birds of a Feather: Jeff and Slater.
- Comic Sutra: "Mexican Halloween", a sexual position according to Chang, knowing nods from Troy and Jeff.
- Dem Bones:
Pierce: Those floating Mexican skeletons are right! My life is over!
Jeff: Well, when we go to floating skeletons with our problems, we get what we pay for, don't we?
- Die for Our Ship: Invoked in-universe by Shirley. She obviously ships Britta/Jeff and doesn't like Slater getting in between them and proceeds to wreck Slater's car and office.
"You're stealing Jeff from a good woman!".
- She comes to her senses eventually, however, and realises a lot of it was taking out her own internal issues.
- Ecstasy Is LSD: The pill Star-Burns gives Pierce has him acting like he's rolling on ecstasy... then he starts hallucinating Annie making cracks about his age as talking calaveras fly around.
- He does take a lot of medicines, could be unfortunate drug interactions.
- Fake Static: Pierce attempts this when he is unable to turn his phone off.
- Girlfriend in Canada: As revealed during his accidental phone call, Pierce told his mother that he has one.
- Gotta Catch Them All: Annie has a breakdown if everyone doesn't show up to her party.
- Gratuitous Spanish: At the party, Annie keeps peppering her speech with unnecessary Spanish phrases, prompting Chang to shout "You don't need to keep doing that!"
- Halloween Episode
- Hot Teacher: Prof. Slater.
- I Always Wanted to Say That: Troy has some questions he has wanted to ask Batman. Roughly three minutes' worth of questions on the DVD gag reel.
- I Taste Delicious: One of Troy's greatest fears is that he'd wake up one morning as a donut and eat himself without even questioning it.
- Insult Backfire: When Chang mocks Jeff for striking out with Professor Slater, Jeff retorts that Chang wasn't any more successful with her. Chang laughs it off, pointing out that he's, well, Chang, and Jeff by definition should be able to do better than him.
- Lame Excuse: The last time Annie threw a party, everyone left, claiming that they couldn't miss the news. When someone attempts to leave her Dia de los Muertos party with the same excuse, she nearly has a conniption fit.
- Little Known Facts: Jeff's first pick up line.
- Ms. Fanservice
Britta: I hate it when women use Halloween as an excuse to dress up like sluts. (Annie takes off her cape revealing her skintight skeleton costume)
- Mushroom Samba: Pierce descends into one.
- The Only One: Due to the Mushroom Samba.
Pierce: Is Jeff out there? He is the only one that can help!
- Out Run The Fireball: Abed (as Batman) dragging Jeff and Pierce out of the library to Out Run The Collapsing Fort Made Out Of Desks.
- Pity Sex: Played with. Professor Slater first agreed to sleep with Jeff because he made himself seem pathetic, begging and pleading enough until she finally said yes. Subverted in that it never happened in that episode, and instead they first slept together after dating conventionally.
- A Storm Is Coming: Abed points this out during his arrival at the party.
- Strange Minds Think Alike: After Abed and Troy's conversation in the tag about the possibility of eating yourself if you woke up to discover you were a donut.
Troy: It's cool to know other people think about this stuff too.
- Teacher/Student Romance: A rare example where the student (Jeff) is older than the teacher (Slater).
- Throw It In: Danny Pudi improvised the ending Batman voiceover as a placeholder, but the crew decided to keep it.
- What Could Have Been: The original draft had Shirley crapping in Slater's desk. Yvette Nicole Brown considered it out of character and requested the rewrite.
- What the Hell, Hero?: When Jeff finally snaps and tells his friends to get lost and leave him to seduce Slater, they — and Slater — are quick to point out what they think of this (although Troy subverts it):
Way to go! Abed:
I know I'm not Batman; you could try not being a jerk
She's pretty hot. Jeff: [Slinking back over to Slater]
Well, where were we little doggy? Slater:
Unseemly. [Walks off] Jeff: [Deflated]