Who’s the biggest diva on the <i>Game Of Thrones</i> set? It’s not who you’d expect.

We’re waiting in a photo studio in West Hollywood for the creators of Game Of Thrones, Messrs David Benioff (above, left) and Dan Weiss (above, right). They’re late but, like winter, they’re coming. With the premiere of season six of the world’s biggest TV phenomenon only days away when we meet, the Two Ds, as they’re known, are busier than ever. Have they – aha – hit a wall?

Game Of Thrones is now such a success that it’s easy to forget its rocky start. HBO was in two minds about the pilot. All those characters and settings. The complicated world of the story. Who and what was it even about, anyway? But it eventually gave the creators a season to prove their worth. “That first year felt very probationary,” Mr Benioff told The Hollywood Reporter. And then it took off. With every episode and every season, the audience grew like the armies of Daenerys Stormborn. This is a show that shoots in Northern Ireland, Spain and Croatia, with crews of up to 750 people. It’s a monster.

Season six may be the most anticipated of all. Epic stories are converging with lead characters – Arya Stark, Jaime Lannister, Daenerys, Cersei, Bran, Sansa. And this is the first season in which the show departs fully from the books, forging its own path. They’ve been diverging for a while, but now it’s complete. As fans know, the books’ author Mr George RR Martin still hasn’t finished his latest instalment, The Winds Of Winter.

So we’re all wondering: who’s going to get slaughtered and in what gruesome fashion? Will the dragons torch the armies of Westeros? Will Arya and Hodor finally... Ah, here they are now. Two tall, Caucasian men marching in – White Walkers, if you will – both glued to their iron thrones, sorry, iPhones.

Let the Game begin.

How big is your cast at this point?

Mr Benioff: I haven’t counted, but on our call sheets everyone gets a number. Peter Dinklage [who plays Tyrion] is number one, and we’re up to, I think, 544 now.<br> <br> Mr Weiss: Yeah, 544. I remember that guy. Total dick.

Tell us your favourite Mr Peter Dinklage story.

Mr Benioff: On Episode 209, he had to spend every night standing around in the dark, in <a href="http://www.mrporter.com/journal/the-edit/how-to-look-good-in-the-rain/337">constant 360º rain</a>, covered in mud for 10 hours. For weeks on end. But there was never a complaint. He would pose for prospective metal album covers with his <a href="http://www.mrporter.com/en-gb/mens/clothing/coats_and_jackets">armour</a> and his <a href="http://www.mrporter.com/journal/journal_issue50/3#1">axe</a>.

When you started to catch up with the books, did you consult with Mr George Martin to find out what he was writing?

Mr Benioff: Yeah, it’s a constant dialogue. We go to see him in Santa Fe to ask about what he’s planning and that’s very helpful. But George always says there are two kinds of writers: gardeners and <a href="http://www.mrporter.com/journal/the-portfolio/the-skyliners/345">architects</a>. Architects plan everything, they make blueprints, while the gardeners plant seeds and watch them grow. He’s a gardener, so he lets the story take him where it will. Which means that once we caught up, he couldn’t tell us what was going to happen, because he didn’t know yet.

Does he get upset when you diverge from his books?

Mr Benioff: He loved our scene in season two where The Hound and Bronn meet each other in that tavern…

Where there any changes he didn’t like?

Mr Weiss: It’s hard for George. When we send him outlines of the season, he says it’s like looking through a <a href="http://www.mrporter.com/en-gb/mens/lifestyle/cameras">strange lens</a> at the things he’s working on. Especially when we cast actors who are different from the mental image he has.

Such as?

Mr Benioff: Dany [Daenerys] was meant to be taller. Littlefinger was meant to be smaller. Xaro was meant to be a lot smaller – and feminine.<br> <br> Mr Weiss: And the throne’s different, too. The throne he imagined was much bigger. You had to climb up stairs to get to the seat, but it just wouldn’t work on TV.

He’s late on his book. Does he ever call and say, “Listen, guys, I’m a bit stuck...”

Mr Benioff: No, no, no. The books are entirely George’s.

You’ve shot some pretty visceral scenes. We’re thinking of when Cersei does that naked walk at the end, and the woman spits in her face...

Mr Benioff: Yeah, I’m surprised Lena [Headey, who plays Cersei] didn’t throw up.<br> <br> Mr Weiss: It was just some fake spit thing. There are experts who make that stuff. Fake poop, too.

Was it hard to persuade her to go through all that?

Mr Benioff: That was a rough two-day shoot. But Lena had known that scene was coming for a long time. It’s a remarkable scene. She’s not the kind of actor who stops weeping when we say cut. Whatever she was accessing, it felt very real. She’d gone somewhere dark.<br> <br> Mr Weiss: She was probably thinking about the fact that she had to have <a href="http://www.mrporter.com/journal/journal_issue145/6">dinner</a> with us afterwards.

What’s the most challenging scene you’ve shot?

Mr Benioff: It’s in season six, actually. There’s a big battle that involved 60 horses. And horses are dangerous. They can freak out. So, of course, we shot a scene with a bunch of horses thundering towards one of our characters and pulling up short. It’d be so easy to fake with visual effects, but for some reason we didn’t. And I remember thinking, “Oh god, that actor would be expensive to replace.”.

Are horses as demanding as actors on set?

Mr Weiss: The <a href="http://www.mrporter.com/journal/journal_issue88/5#1">bear</a> in season three was more demanding. If he did a good take – I’m not joking – everyone on set had to clap: “Good job, Bart!” He’d only work for 10 minutes, then he’d go back to his trailer where he <a href="http://www.mrporter.com/journal/journal_issue103/7#1">listened to country music</a> really loud, because it calmed him. And he needed a constant supply of whipped cream pies. Total diva.

Do you take a perverse pleasure in killing series leads?

Mr Benioff: I like killing the pretty boys because it makes my wife so angry. So <a href="http://www.mrporter.com/journal/journal_issue97/1#1">Robb Stark</a>, <a href="http://www.mrporter.com/journal/the-look/mr-kit-harington/317">Jon Snow</a> – they were good.

Jaime Lannister needs to watch his back.

Mr Weiss: He sure does. What a dick!<br><br>Mr Benioff: The Danish dick!

When you’re going to kill off a key character, do you show up on the actor’s doorstep in uniform?

Mr Weiss: No, it’s a phone call. The Death Call. People know that if you get a call from the two of us at once, it means you’re going to die. It’s the bell tolling.<br> <br> Mr Benioff: Except we did call Nikolaj [Coster-Waldau, who plays Jaime Lannister] once about something else, and it freaked him out.

Do you know how many more seasons are left?

Mr Benioff: Yes, but I’m not allowed to tell you.

Do you feel an obligation to surprise people with the ending?

Mr Benioff: Not really. Maybe for us, the surprising ending is a non-surprising ending. Such as the <i>Breaking Bad</i> ending – that was great, it really worked. But it wasn’t shocking.<br> <br> Mr Weiss: We can do both, though, because we’ve got so many characters and plot lines. We won’t have just one ending. It’ll be a mix.

But you know how it ends?

Mr Weiss: We figured it out by season two. It’s like an unfocused image that gradually comes into focus as you get closer.

Go on...

Mr Weiss: Basically, we started with the ending – Hodor sitting on the Iron Throne – and worked backwards from there.

Season six of Game Of Thrones is showing now