From KCRW Santa Monica and KCRW.com, it's The Treatment.

Welcome to The Treatment. I'm Elvis Mitchell. It's always fun to have old friends come back and especially great, generous old friends of the show.

One of them is our old friend Vigo Mortensen has been singing across from me.

Of course, he's a star of the film Captain Fantastic.

Vigo is always good to see here.

It's good to be here.

Nice to see you again.

And what I think I've come to love so much about what you do as an actor is, it's interesting.

You create these internal narratives for your characters, don't you?

You basically create a story for them.

You build like a story, and tell me about the story you built for your character and Captain Fantastic.

I mean, I basically just asked myself what happened before, page one in the script,

meaning, you know, what was his life?

Just to give myself an idea, a leg up, and, you know, what was his life? Just to give myself an idea,

a leg up, and, you know, any surprise comes in my way during shooting, I can react as the character

because I know what his history is, and I enjoy making that up. What happened? He was born, where?

What were his parents like? What was his upbringing, etc.? Until page one.

For Captain Fantastic, know differently.

I mean, the script is one of the best ones I've come across,

one of the best original screenplays I've ever read.

That's a very layered, complex, a lot of characters.

It's a big task that Matt Ross,

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