It also happens to be Bairds favorite novel from theTrainspottingwriter.

In creating such a vivid and uncouth character study, Baird spent years rearranging that crucial story.

And he was kind enough to sit down and talk to us about it last week.

Plus, could the loose literary sequel,Crime, be on the horizon with up-and-coming star Jamie Bell?

Can you talk a little bit about the first time you readFilthand what it meant to you?

I didnt even realize what it was.

I thought what the hell is that!

I was really taken aback by it.

I realized it was Irvine Welsh who wroteTrainspotting, and [I read it].

I thought, Oh my gosh, this is incredibly dark, but very, very funny.

When it came to do the film, I had met Irvine a good 10 years after that.

Just a big slap in the face to get a reaction.

Because that is what you do art for: to get a reaction, whatever the reaction is.

So, seeing that image was the big thing.

What emotion does Bruce Robertson evoke for you?

Pity, I think.

He has become this monster.

So, its a bit tragic.

I always think ofFilthas a tragic love story.

Its about a guy whos lost love, hes lost his wife, and hes lost his daughter.

He doesnt love himself anymore, and because he doesnt love himself anymore, he [becomes] sociopathic.

He doesnt have the capacity to feel anymore.

So, its pity really.

When you met Irvine in I believe 2008

Thats right, yeah.

Did you know that you wanted to make the film?

Well, I think when I met him that I wasnt expecting to meet him.

It was just by chance through a friend.

So, I wasnt going to pitch him about the film.

It was just sort of a coincidental meeting.

I never thought itd be a reality that this book would be available.

I always thought somebody would have the rights for it.

I dont know if the options available or blah blah blah.

And he said, Oh, its funny, because it just became available.

Whoever had it just ran off.

As soon as I said that, it was just likeboom.

And we just seemed to be very similar people and have a very similar sensibility.

So, it wasnt that difficult to convince him of the passion I wanted to bring to it.

In this, you zero in on Bipolar Disorder.

Is there a reason for that?

Well, I just think it makes him more interested in terms of what was making him crumble.

I have got a lot of experience with that.

I grew up with somebody close to me whos got that condition, as did James [McAvoy].

So, that was really why.

I want it to be larger than life, and I want it to be sort of arresting.

A big influence for me isA Clockwork Orange, and I saw Bruce as a similar character to Alex.

And theres a lot of little sort of references to that inFilth.

I suppose that is the reason why.

James McAvoys fantastic in this.

This is one of his best roles.

How did you cast him?

How did the two of you develop this role?

And we were like, Hes not the obvious choice, but well meet him of course.

As soon as I met him, I realized how edgy he is in real life.

Hes got more of an edge than people imagine.

Hes a lot more like Bruce Robertson than Charles Xavier [Laughs].

Hes got a great sense of humor, and hes got a real edge.

So, he knew what he was doing; it was all on the page for him.

But he had to bring it off the page.

So, we spent a lot of time in rehearsals working it out and really finding it.

He needed to know that he could trust me.

So, the big thing was getting to that place, I suppose.

You say he is more Bruce than Xavier.

Since youre both Scotsman, can you relate to some of Bruces tendencies?

Yeah, I totally do!

The Scots have got a real dark sense of humor, a real playful sense of humor.

Theres a lot of substance abuse in Scotland.

Did James or anybody in the cast have any reservation about how dark the material could get?

We wanted to push it even further, we really did.

The thing about it is its called filth.

You know what youre coming into as well.

But also filth means police back home.

Thats what they call them: the filth.

So, whoever signs up for an Irvine Welsh adaptation knows what theyre getting into.

So, I think the cast wanted to push it further.

Were making a movie, not a documentary.

I think Bruce is one of them [Laughs].

It just changes him, as well as the mental illness.

So you do think he had the good intentions or that he didnt start out where he is now?

I dont think he started out like that, no.

The whole chance of redemption is there.

I think the Joanne [Froggatt] character is the only one who sees him as a human being.

So, I think deep down there is an element of goodness in it.

The movie has a lot of surrealism.

I didnt catch that.

I should have caught that.

In the script it was written as Foreigners I Want to Know What Love Is, yeah?

And then I was thinking about it, Hmm, its not quite right.

And he says, Oh, I know David Soul, Ill give you his number.

Would you like to do a sort of cameo in the film and sing your own song?

And he was like, I dont understand what youre talking about, but yeah lets do it!

The level of breakdown at that particular point.

[Watch the scene here]

I know there is an unofficial sequel to this calledCrime.

First, what did Irvine think of this movie?

And are you interested in adaptingCrime?

Also, has Jamie Bell discussed that with you at all?

Which is a lovely thing for a novelist, a very humbling thing for a novelist to say.

In terms ofCrime, I would love to doCrime.

But its set in Miami.

His character goes to Miami.

Its more of a thriller.

Its more of an obvious movie thanFilth.

Its not got the symbolism.

Its almost likeLeon, you know?

Its almost a relationship between him and this young girl hes trying to save.

And I would love to doCrimeat some stage, yeah.

If he goes to Miami, I assume he did not kick his drug habit.

Nope [Laughs]!

Thank you very much.

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