Emma Thompsonknows that sometimes it’s good to be bad.
“It’s very existential,” she tells EW of assuming such a grotesque form.
“It’s an out-of-body experience.

Dan Smith/Netflix
I don’t feel a desperate need to get away from myself or anything.
When the physicality helps you to find who this person is, it’s a great privilege.”
ENTERTAINMENT WEEKLY: You have a very impressive CV of literary-related work.

Dan Smith/Netflix
Where doesRoald Dahl’sstorytelling rank for you?
EMMA THOMPSON: I grew up being deeply influenced byCharlie and the Chocolate FactoryandJames and the Giant Peachin particular.
I love Dahl’s writing and I read like Matilda as a child.
I mean, not the Dostoevsky, but I read all the time.
You couldn’t get me out of a book.
I identify with that part of her.
I’m so grateful that I read such wonderful writers when I was a child.
There’s a great book actually by a British author called Francis Spufford calledThe Child That Books Built.
That’s such a wonderful image.
I can remember being inside those books.
I can remember stories I read when I was very young and being actually inside them.
It is really an escape from your life or a way of experiencing something different inside your imagination.
It’s such a magical thing for a child to be able to do.
What about children’s literature specifically fascinates you or makes it stand apart for you?
I’m not sure.
I’ve got a feeling that it’s to do with my father.
It was very popular with adults, even though it was for children.
And he said, “There’s no such thing as children.
They’re just people who haven’t lived as long as we have.”
They might have less experience, but they want to know what the real world is.
As a developing child with a creative bent, I experienced watching my creative parents doing very different things.
Is that part of the appeal of Dahl for you specifically?
His stories are weird and scary and don’t sugarcoat anything.
I never forget the cruelty of Aunt Sponge and Aunt Spiker inJames and the Giant Peach.
They’re really horrible to him, you know?
All the great authors, their stories weren’t written down for children.
How much input did you have into your look and this version of Trunchbull?
Oh, a lot.
They were a fantastically collaborative team.
They had all sorts of plans.
I will check that that this version of my blue eyes will not be nice.
I promise you, you won’t miss the contact lenses."
And he really didn’t.
They were thinking to put a great big prognathis forehead on me.
I need this bit to express her.
It’ll look weak.
I need a strong nose.
We worked it out like that, with what’s the least we can get away with?
How did this compare to Nanny McPhee in terms of hair and make-up and transforming?
Why does her physical appearance change?"
Because we can’t say that ugly is bad and beautiful is good.
That’s not the point.
Because she’s good when she arrives.
She just happens to look frightening.
It’s about the way in which she’s seen.
Has she changed or have you changed?
Because Nanny McPhee doesn’t change.
But within she’s the same.
And I suppose Trunchbull is the physical expression of her internal rage and despair.
It’s quite a different form of mask work.
I found a really interesting history of a woman called Edith Sitwell, a 1930s poet.
That’s how I worked it.
It really helped because it meant it wasn’t about the children, it was about her.
She’s an Olympic champion in the hammer throw, a skill she uses to punish children.
Did you have to do any sort of training for that?
We had to have that as well.
That shot is a combination of me and the professional, Justin.
We had a prosthetic, pretend child who was fantastically heavy actually.
I had to say them, “I can’t throw this child.
She’s too heavy.”
She was made of a very heavy kind of plastic.
But they’ve done a wonderful job on it because it really does look so convincing.
Is one more intimidating or challenging than the other?
On a personal level, absolutely.Leo Grandeis a totally different revelation.
These two strange bookends.
Someone who’s so, so vulnerable, Nancy Stokes, and someone who’s also actually deeply vulnerable.