Mark Ruffalohas taken a turn.

Im so sick of being so well-behaved, he says.

I just want to take the ship as close to the reef as I can without actually crashing it.

L-R: Joaquin Phoenix and Pedro Pascal in ‘Eddington’

Emma Stone and Ruffalo inPoor Things.Atsushi Nishijima/Searchlight Pictures/Everett Collection

And maybe Ill crash it too.

I dont give a sh*t anymore.

Even his Marvel franchise Hulk is deeply loveable.

So, it was hard to imagine Mark Ruffalo as a cad.

A proper, moustache-twirling, lock-up-your-daughterscad.

But then cameYorgos Lanthimoswith hisPoor Thingsscript.

I was like, I dont know if Im the right person for this, he says now.

Yorgos said, Yes, you are.

He just laughed at me, basically.

Consequently, his psyche implodes in shock.

Its an incredible role and an utterly unexpected choice for Ruffalo.

Has Lanthimos ever said how he knew Ruffalo had it in him?

The last time I talked to him, he was just like, Youre a terrible dancer.

Lanthimos gave Ruffalo no notes at all.

Theres a thing they do calledTriptych.

And theres one particular thing he showed me [inLe Salon].

Its this beautiful dance-acting-movement piece.

Their mouths never leave each other, and its the most beautiful moving, sexy thing.

Yeah, he didnt give me any notes.

He wasnt like, I think this character is like this.

He just handed me that.

And, during shooting, there continued to be no notes.

One sign that Ruffalo was on the right track was if Lanthimos laughed.

The other was if Lanthimos said the words, Thats enough of that.

Willem was like, Youre really going to do that?

But I was kind of like, F*ck it.

The role stirred something distant and long-forgotten in Ruffalo.

This is a part that no one wouldve expected me in.

If Ruffalos previous roles were restrained as he puts it, its tempting to wonder what influenced that outlook.

Back in 2001, he was riding high.

He was on the set ofThe Last Castlewith James Gandolfini and Robert Redford.

His wife Sunrise Coigney was about to have their first baby.

Then, one night, he had a strange dream.

In it came a direct message of doom.

It wasnt even a voice or a scene playing out, Ruffalo says.

It was just, You have a brain tumor, and you have to deal with it immediately.

It was just this clear knowledge.

That knowing was so strong that Ruffalo got a CAT scan.

And hedidhave a brain tumorone the size of a golf ball.

People were like, He has AIDS.

Hes a drug addict, because I disappeared, he says.

There were all these rumors going around Hollywood, and I had to drop out.

I was cast in an M. Night Shyamalan movie.

And it just all evaporated.

I thought I was going to die.

We had a baby, and then 10 days later, I had my brain tumor removed.

I had this newborn, and we were starting a life, and my career was now suddenly gone.

I looked at death, but I also looked at not being an actor.

What am I going to do?

So Ruffalo fought back, and then some.

I was just so much more desperate, he says.

I love acting, but I was also like, Huh.

Have I reached what Im able to do now?

The internet and social media brand you, and it just feels very oppressive in a way.

But the wild-card character has peeked through a little in his past choices, he says.

He notes there was even a flavor of Duncan in his 2010 filmThe Kids Are Alright.

That role was sort of in the line of Duncan.

Ive gotten to play some characters that are reminiscent of Duncan, like the baby seeds of Duncan.

EvenYou Can Count on Me, that character, theyre these neer-do-wells that you sort of love.

And so, they were really aware of that conditioning, and the movie slaps that in the face.

I have women friends that I know that say, I love Duncan.

I was really pulling for him.

But at the end I was like, oh, god, poor guy.

I felt a lot of sympathy for him.

Its another pretty brave performance, he says.

Its pretty far out there, and he is not a good guy.

Hes a proto-fascist a little bit.

These men, theyre up for discussion right now.

He pauses and checks himself.

He cant help it.

Im a guy, so I might be talking out of my ass, he says.