We get a successful television series or something, and next season they give you less time and less money, which is something I've never really understood. That doesn't happen with Game of Thrones.

When you get to a certain age, the work begins to thin out.

But the quality of writing in the series [game of Thrones] is paramount. That's probably why all of us are involved in this and all of us are quite so loyal to it, because we don't have to expend a lot of energy trying to make a silk purse out of a pig's ear. The quality of the writing is really good, and that's what makes playing a character so enjoyable, whether he's heroic or villainous.

It starts with the writing - which is really, really good. And the production values are phenomenal. HBO and Sky have spent money on it, and you get what you pay for. This has money put into it properly - not lavish amounts - but as each season is successful, they maintain the money that's being spent to maintain the quality.

I am made Hand of the King which gives me an enormous amount of power, which I use quite ruthlessly - but skilfully - and Dame Diana Rigg joins us [playing political mastermind the Queen of Thorns] and we have a couple of really good sparring moments.

There is a huge fan base, they're very knowledgeable and very loyal. I was astonished - before I started working on the series I didn't know anything about Game of Thrones. I hadn't heard of the books. When it started going out, people were coming up to me in the street saying [fake cockney accent] "oh, Game of Thrones, f------ wonderful.

On an independent film you're lucky if you get one, but ostensibly the job is the same. There's very little difference, apart from the knowledge that there's a captive audience at the end of it - which you can't always guarantee with a movie.