I've got a dozen condoms in my quiver.

- Oh, hey guys.

- Hey, sorry we're late.

- Late? It's 7:05.

- And you said the party starts at seven.

- Well, yeah, when you start a party at seven,

no-one shows up at, you know, seven.

- It's 7:05.

- Yes. Yes it is.

Okay, well, um, come on in.

- What, are all the girls in the bathroom?

- Probably, but in their own homes.

- So what time does the costume parade start?

- The parade?

- Yeah, so the judges can give out prizes

for best costume, you know, most frightening,

most authentic, most accurate visualization

of a scientific principle.

- Oh, Sheldon, I'm sorry,

but there aren't gonna be any parades or judges or prizes.

- This party is just going to suck.

- No, come on, it's gonna be fun,

and you all look great,

I mean, look at you, Thor, and, oh, Peter Pan,

that's so cute.

- Actually, Penny, he's Rob-

- I'm Peter Pan!

And I've got a handful of pixie dust with your name on it.

(blows)

- No, you don't.

Oh, hey, what's Sheldon supposed to be?

- Oh, he's the Doppler Effect.

- Yes.

It's the apparent change in the frequency

of a wave caused by relative motion

between the source of the wave and the observer.

- Oh, sure, I see it now, the Doppler Effect.

Alright, I've gotta shower,

you guys, um, make yourselves comfortable.

- Okay.

- See, people get it.

(party goers chatting) (upbeat music)

- Mmm, by Odin's beard, this is good Chex Mix.

- No thanks, peanuts,

I can't afford to swell up in these tights.

- I'm confused.

If there's no costume parade, what are we doing here?

- We're socializing. Meeting new people.

- Telepathically?

- Oh hey, when did you get here, Hi!

- Penny is wearing the worst Catwoman costume

I've ever seen, and that includes Halle Berry's.

- She's not Catwoman, she's just a generic cat.

- And that's the kind of sloppy costuming

which results from a lack of rules and competition.