The Witches (Put them everywhere and you have a story, if not, you are dead to me)

The Witches...
The Weird Sisters.
Gah.

So all I ever hear about them is they are the embodiment of pure evil.
But what does that mean?
Well, for starters they worship Hecate.
For those not in the know, she is the most badass pagan goddess of magic...ever
They also curse a woman's husband, wracking his ship with storms so that he cannot sleep for weeks and (almost) never sees his destination.
Why do they do this to him?
Because his wife refused to give a witch a nut....EVIL

So these are the ladies/men (they have beards) that kick off the whole shindig.
But why?
Why does Shakespeare start with the withces?

I will lay some pretty heavy literary/story ideas on you.
In most things there is a what we call "PROTAGONIST"
(https://youtu.be/FxKtZmQgxrI?t=2m7s)
Watch Red Letter Media's video for reference here.
A protagonist is the main character, the one we ask the dramatic questions of, and illustrates the ideas of the story.
Now in Macbeth, we go on a wild limb here and say Macbeth could be the protagonist.

Now, who is the antagonist?
...............
I have seen/read/talked about this play for years and no one has satisfactorily answered this question.
(It is the witches)

The play starts with the antagonists: the women of wyrd, of fate!
Now some may argue it is Lady Macbeth. You're ignorant. It isn't your fault, you were lied to by your high school English teacher who also taught your professional director.
Lady M does not show up until the end of Act I, she kills herself by the middle of Act V (spoilers). She does not even enter the equation as far as antagonists.

You might say it is Macduff.
And you could make a case for it; I have.
But Macduff does not appear in the play until Act II; he is not even foreshadowed as far as being important until Macbeth sets his sights on him in Act III.
Until the murder of his family (spoilers) there is nothing setting him up as the righteous avenger that we need to kill the treacherous Macbeth.

Who does that leave? Banquo? Lennox?
Hint: It is the witches.

Now some are clamoring: what about the final climax?
What now?
The final climax? There is always a boss battle between the villain and the hero!
That is Macduff!
Except Macbeth totally whoops Macduff.
Seriously, read it.
Macduff is not even a problem.
In the middle of the fight Macbeth has a monologue:

Thou losest labor. As easy mayst thou the intrenchant air impress as make me bleed; let fall thy blade on vulnerable crests, I bear a charmed life which must not yield to one of woman born.

He is winning!
It is not until Macduff reveals he is not of woman born, skating by on a technicality that Macbeth is foiled and ultimately killed.
And who does he damn? The witches.
This is a move against fate against the witches that Macbeth is fighting against.

So now we have our villains for the piece.
What makes them so villainous?
They appear in like three scenes?
Wrong. So wrong.
They are in every scene.
What did he say?
EVERY SCENE.

The witches are always there.
That is how they know everything.
They move like the air, they should be everywhere.
Listening.
That is how they make prophecy.

How did they know he would be Thane of Cawdor? They heard it.
Why did Macbeth see a floating dagger? They held it.
Whose voice did Macbeth hear say "Sleep no more"? Theirs

They manipulate the information and therefore the people.
But how could they?
They aren't there during the big scenes!
They are the murderers.
Yeah, the guys who murder Banquo and miss Fleance.
Oh they murdered one of the best fighters in the world of the play, but miss his hysterical son?
They let him go to alienate and make Macbeth more paranoid.

In Act IV Macbeth travels to the witches and asks if Banquo's children will reign.
They show him a line of kings and then vanish.
Macbeth asks Lennox where they went and he says

I didn't see them, but two or three men showed up to tell you Macduff has fled to England.

Hint: witches.
They kill Macduff's family.
They kill Lady Macbeth.

That is why they are pure evil.

Why do they do this you may ask.
For the thumbs.
I am not kidding.
In almost every incantation they need blood, body parts, entrails from murderers, thieves, traitors, etc.
Where do they get that?
From war.
Bloody, civil war.
WAR with a capital WA-

My theory is they are parasites, living off the detritus of conflict and whenever one comes to peace, they begin a new one.
The original Thane of Cawdor was probably theirs, Macbeth was certainly theirs, and soon Banquo's little Fleance will be too.
The witches man.
If they are not the highlight of the whole show, you are doing it wrong.

I should say that all of this is my opinion and none of it grounded in an objective reality of the text.
But if you want me to say that, then you have no business being in theatre.