Cut to Lupin's classroom, day. The bell rings, signaling the end of classes for the fifth years. Harry enters.

LUPIN: (O.S.) Good evening, Harry!

We see Susan and Neville standing by grindylow cage. Lupin in background.

SUSAN : Oh, hey, did Ginny get to class all right?

HARRY: (distracted) What? Oh, uh, yeah. I think so.

Harry walks farther into the room. We see Ron sitting at a large round table holding a pair of Quidditch balls, one in each hand.

RON: Respect the bludger. And tame the quaffle!

Hermione passes by en route to her desk/ workstation.

HERMIONE: That's still funny, Weasley.

Hermione goes behind the desk. Lupin looks in the box of donuts, takes one out, takes a bite.

HARRY: So, uh, no research? Nothing going on? Monsters or whatnot?

Lupin and Ron shake their heads "no," continue eating donuts.

HARRY: Good! Good. (awkwardly) Uh, so, did anybody ... uh ... last night, you know, did anybody, um ... burst into song?

Lupin stops chewing. Everyone stares at Harry for a moment.

RON: Sweet Merlin's new shoes!

Susan, Neville, and Hermione rush over. Everyone talks at once.

SUSAN: We thought it was just us!

LUPIN: Well, I sang but I had my guitar...

NEVILLE: It was bizarre. We were talking and then it was like-

HARRY: Like you were in a musical!

NEVILLE: Yeah!

LUPIN: That would explain the huge backing orchestra I couldn't see and the synchronized dancing from the house elves.

SUSAN: We did a whole duet about cauldron washing.

HERMIONE: And we were arguing and, and then everything rhymed and there were harmonies and the dance with coconuts.

SUSAN: There was an entire verse about the cous-cous.

RON: It was very disturbing.

[All the above is everyone talking at once.]

LUPIN: (to Harry) What did you sing about?

HARRY: (pauses) I don't remember. But i-it seemed perfectly normal.

RON: But disturbing. And not the natural order of things, and do you think it'll happen again?

LUPIN: I don't know. I should look into it.

SUSAN: With the books.

NEVILLE: Do we have any books on this?

RON: Well, we just gotta break it down. Look at the factors before it happens again. Because I for one-

[Lupin begins to sing, interrupting Ron.]

Song: "I've Got A Theory"

LUPIN:
I've got a theory
That someone's schemin'
That Snape is schemin'!
No, something isn't right there.

SUSAN: (looking at Lupin flirtatiously)
I've got a theory
That I am dreamin'
Come on and pinch me. I think you will know just right where.

[Neville was doing "jazz hands" but looks shocked at Susan after that.]

RON: I've got a theory we should just get out.

HERMIONE/NEVILLE/SUSAN/RON:
It's getting eerie, what's this cheery singing all about?

NEVILLE:
It could be snitches!
Some evil snitches! [sees Susan's and Hermione's expressions]
Which is ridiculous, 'cause snitches are inanimate,
Until we put a charm on them, and Harry flies and catches them,
And I'll be over here. [sits]

RON: I've got a theory! It could be spiders!

Silence. The others just stare at him. Sound of crickets chirping.

NEVILLE: I've got a-

Suddenly the tune changes to a frantic hard-rock beat with electric guitar and a roving spotlight that waves crazily over Ron.

RON: (shrieking a la Kurt Cobain)
Spiders aren't just harmless like Hermione supposes!
They've got them hairy legs and imagine all the toes-es
And what's with four pairs of eyes?
What do they need such good eyesight for anyway?
[playing air guitar]
Spiders!
Spiders!
It must be spiders!

Fireworks go off all around him, then the smoke clears away. The others continue simply staring.

RON: (back to original melody)
Or maybe goblins.

SUSAN: (quickly sits down beside Lupin and opens a book)
I've got a theory Harry'll fix this fast.

SUSAN/LUPIN:
But he dearly does need Sirius who now is passed.

Lupin gets up, starts to climb the stairs to the extra storage above the classroom.

HARRY: I've got a theory. It doesn't matter.

Lupin pauses, turns back. Everyone looks at Harry.

HARRY:
What can't we face if we're together?
There's no one like Hermione for clever.
And Voldemort?
Well I'm not scared.
You're all worry-warts!!
Why should we care?

ALL EXCEPT LUPIN:
What can't we do if we're all in it?
We'll trash it up and then we'll bin it.

Harry looks at Lupin throughout this. Lupin watches him too and finally joins in.

ALL:
I think we may
Find out why it came,
What can we say?

HARRY: God, this is lame.

Lupin smiles, comes down off the staircase.

ALL: What can't we face if we're together?

LUPIN: (descant) What can't we face...

ALL: The core to Harry's wand is Phoenix feather.

LUPIN: ...is Phoenix feather...

ALL: There's nothing we can't face.

RON: (sits) Except for spiders.

End of song "I've Got A Theory."

HERMIONE: See, okay, that was disturbing.

SUSAN: (sits) I thought it was neat.

HARRY: So what is it? What's causing it?

LUPIN: I thought it didn't matter.

HARRY: Well, I'm not exactly quaking in my regulation Hogwarts robes, but there's definitely something unnatural going on here. And that doesn't usually lead to hugs and puppies.

HERMIONE: Well, is it just us? I mean, is it only happening to us? (Harry turns away) 'Cause that would probably mean a spell or-

Harry goes to the window, opens it. He looks down onto the grounds. Cut to the grounds. Hagrid stands near his hut holding a butterfly net and there are short, furry, bipedal creatures with goat-like feet and monkey-like hands running all around him.

HAGRID: (sings) They let ... the porlocks ... out!

We see a whole crowd of people (his Care of Magical Creatures Class) standing in dance formation holding similar nets. They do a synchronized dance, waving them around.

CMC CLASS: (sings) We let the porlocks out!

Harry turns back to the room, closes the window.

HARRY: It's not just us.

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