The countdown to "Game of Thrones'" second season premiere is on. The lavish fantasy series returns to HBO on April 1 with the episode "The North Remembers." And to remind viewers of the complex circumstances of the Seven Kingdoms at the end of last year, the first season was released on DVD and Blu-ray on Tuesday, and it's also now available on iTunes.

"Thrones" executive producer and series co-creator D.B Weiss took a few minutes to talk about the first and second seasons and some of the special features of the DVD set.

Are you still in post-production on the second season?

Yes, we are in post-production and getting it all ready as quickly as we can for the drop-dead dates when they pry it out of our cold, dead hands. We’ve got a couple of episodes locked and done and in the can, but we still have some work to do on the back end.

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In the first season you included some elements from the second book. Once you start making changes like that, do you find you have to make more changes or is Martin's original narrative pretty malleable?

Our approach has always been what we pitched to George at the very beginning: We're adapting his entire series. The changes we make, taking something from one book and putting it in the middle of events from another book, are always at the service of the series as a whole -- both George's series and our series. Oftentimes an event from Book 2 will serve as a better end point for a character in Season 1 than it would as a starting point in Season 2.

This year there are definitely things we took from Book 3 and pulled them back a season and there are things we hold off on introducing from Book 2 to put in a later season and there are things, regrettably, there's just no room to include at all. George, luckily, isn't just a seasoned novelist. He's also a seasoned television writer and he knows how the sausage is made and understands the sacrifices that often need to be made in the service of preserving the impact of a show as a whole.

One of the scenes from the first season that really leaves a lasting impression is of Tywin Lannister (Charles Dance) skinning a deer.

That was a real deer. It was purchased from someone who sells stags and Charles Dance learned on the day how to skin a deer. You never would have known. It seemed like he'd done it his whole life.

Another scene that raised eyebrows was the scene with Littlefinger revealing his thoughts before two naked prostitutes as they writhe in bed together. What was the thinking behind that scene?

It's a challenge you face getting inside a character's head when you don't have any of the novelistic devices George has at his disposal. Many of which are the equivalent of voiceover, telling us what a character is thinking. The Littlefinger scene was born from the necessity to learn who this person was behind the mask, and unfortunately this is someone who's such a confident total game player that the truth about who he really is and what he's really about is something he's not going to reveal to the other game players he encounters over the course of his daily life. In this situation, the prostitutes serve as psychiatrists, which is the conception behind that scene and setting it where we set it and doing what we did with it.

One of the more impressive features from the DVD set is a motion comic explaining the various religious beliefs in this world. Do you oversee that as well as the series?

We were definitely very excited and involved with all aspects of DVD production. Credit for [the motion comic] goes to Bryan Cogman, our story editor and writer who also wrote those, and Will Simpson, who did all the artwork. He also does our storyboards and is a respected and noted comic artist in his own right. And the whole DVD team who wrangled the cast. We were very pleased with the concept and how beautifully it was executed.

Is Bryan the keeper of the mythos on the series?

Bryan's got a very unusual brain. I'd really like to put Bryan up against anyone short of George himself in ability to totally recall every piece of information that exists in terms of the books and show. I imagine somewhere on some wall is a very complicated chart.

There was some buzz online recently about the length of the Battle of Blackwater sequence late in this season. One (mistranslated) interview stated the battle was 16 minutes long -- about a quarter of the episode. How long is the battle?

All I can say is that if I can't quote you a number and David can't quote you a number about how many minutes the battle sequence is in that episode, then nobody else can either. We've definitely put the episode together. We never thought about it in terms of "We need X minutes of this or X minutes of that." We know there's a huge, complex battle to service and we know there's a human drama taking place over the course of the battle we need to service and we're telling the story as effectively as we could with the resources we had, never losing sight of the people involved, which ultimately makes the battle sequence worth watching. Otherwise it's just eye candy.

I don’t remember who said [the number]. I'm sure nobody meant anything by it. I just thought it was funny that a number was quoted and I thought, "Oh wow, somebody is actually timing it." I've watched this episode through maybe 15 times. We certainly couldn't put a number on it.

Are you surprised by which elements of the show fans seem to fixate on?

We've been really lucky there's been a wide base of people who've come to enjoy the show and lots of them are fans of the books and some of them have never heard of the books. And you probably get a slightly different reaction from each group. And you probably get a different reaction within each group. George has his core fan base of readers. It's hardly a homogeneous group of thinkers. They all have their own fiercely held opinions. They often debate at length with each other and anyone else who wants to listen. It's hard to talk about the fans as a monolithic group. There are fantasy fans who love the books and there are auto mechanics who love the show and there are politicians and mixed martial arts fighters who love the show. It's a pretty wide, random base of people. It's hard to know what any group is fixating on or not fixating on.

Do you monitor reactions from any of the many websites devoted to Martin's books?

To be honest there isn't that much time available to us now to spend on that stuff. The time pressures of getting the show ready to air are so immense and all-consuming that it really is two full-time jobs. It's not that we're not interested in what people think; but we don't have a whole lot of time to engage people directly as we might if the show were less production-intensive.

How much downtime do you have after finishing Season 2 before you start writing Season 3?

That would be zero. Zero minutes and zero seconds. By the way, I should point out that we don't have a greenlit Season 3 yet. It's not a foregone conclusion in our minds. But the show needs to operate on the 52-week, maybe 51-week-a-year schedule to get finished.

Are there more visual effects this season?

Visual effects definitely play a much bigger role in the show this season than it did last season. I don’t have a shot count in front of me, but I know those can be deceptive. Lots of visual effects shots are fixes. And one of the great things that we’ve learned this season was how to minimize those low-value fix shots by not needing the fixes to begin with ... how to get the right blood spray that you want in production so you don’t need to add it in later. For every one of those you can save, it’s more money spent on a visual effects shot that people are really going to notice .... But we have such an amazing group of visual effects artists this year that you're sometimes hard-pressed to remember what was real and what was added in later.

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-- Patrick Kevin Day

Photo: D.B. Weiss, right, and David Benioff, center, on the set of "Game of Thrones" with an unidentified crew member. Credit: Paul Schiraldi / HBO