Read on to find out what Gale had to say about the changes this season, the "dark and deadly" world of the show, new zombies, those movie rumours and why we should be prepared for shocks...
We're not going to be on the farm this season, obviously - we've got the prison and Woodbury to look forward to! How does that change the show?
"Well, obviously at the farm there was a safe haven where they really didn't face the daily risk that they had in the first season of surviving, to the same degree. They had to deal primarily with the drama that was developing among the survivors, especially the love triangle, and it gave us an opportunity to really get to know many more of our characters.
"But at the same time, as with the comic books, ultimately no place is safe anymore, and that Shangri-La is overrun, and now they're looking for a safe haven. The group has also been split, so we have Andrea being left behind and obviously at the end of the season saved by this mysterious warrior with a katana sword, Michonne, and we have the rest of them essentially on the road with the reveal of the prison at the end.
"But the new season, especially with our core survivors, is much more of a hand-to-mouth existence. It's not bucolic or pastoral, it's gritty. But to contrast that, we now have Woodbury, in which a town has been sort of created - like the old medieval cities - against the zombie hordes. And we get to see an alternative way of surviving the zombie apocalypse under the Governor. And as you know, a fantastic British actor, David Morrissey, is bringing the Governor to life."
There seems to have been so much buzz about this season with Michonne and the Governor - are you worried about living up to fans' expectations?
"No, absolutely not. I've seen seven episodes and I think that the fans will certainly not be disappointed! We also have the opportunity now to cut back and forth between those two different worlds, the world of the prison as well as the world of Woodbury."
People have been wondering how similar Michonne and the Governor are to their counterparts in the comic books.
"Well, the Governor is a very complex guy. He honestly does believe he's doing the right thing. I don't think he's going to win any 'humanitarian of the year' awards, which was also true in the comic books! I think that fans of the comic will really embrace not only David Morrissey's portrayal of him, but quite a few things that they found so compelling in the comic book."
You mentioned that the Governor is quite complex - it would be so easy for him to be a cartoon villain.
"That's why you cast someone like David Morrissey - he's incapable of playing a cartoon character! I think we take it very seriously; we hire the best actors for these roles, we don't just cast people if they look exactly like the character drawn in the comic book, although sometimes that does happen.
"The show has to remain grounded. The danger and jeopardy to our characters has to remain real. If we put in a dastardly villain who's one-note, that simply doesn't fit within the universe of the TV series."
It looks in the trailer that the Governor and Rick are going to be clashing quite a bit...
"You know what, I don't think they're going to be best friends forever!"
That would be a twist!
"Yes, definitely! We also get to see the dynamic that develops among the other characters, including Michonne - another fantastic actress we've brought on, Danai Gurira, who grew up in Zimbabwe. It's a very international cast!"
I think a lot of people are very excited about seeing her - what can we expect for her and Andrea?
"As Laurie Holden has said, it's the first time that she's been able to develop a relationship with another character that she can bond with. But as with every relationship in our show, it's never just smooth sailing. That's the way life is. This is a mirror of life, but in which you face death at every moment, and always when you least expect it."
After last season, we know no-one is safe - can we expect more heartbreaking deaths and shocks?
"I think you might... I think you might be facing that!"
We should prepare for some emotional moments?
"You know, the world is dark and deadly. At the same time, there's moments of lightness. There's still the love story between Glenn and Maggie - it's not unrelentingly bleak."
Can we be reassured that Glenn and Maggie are going to be okay then? Or should we be preparing ourselves for bad stuff to happen?
"You know, there are no guarantees in this world of The Walking Dead!"
We've spoken a bit about new characters, but there's also a very exciting returning character - I think everyone probably screamed when they saw Merle in the trailer. What can you tease about his return?
"Ahh, Merle! You know, clearly one of our more compelling and dysfunctional characters which - because we have the remarkable Michael Rooker bringing him to life - is not just a one-note racist bully. But he's certainly larger than life and he's deadlier than ever."
So he's not to be trusted?
"You know, I think Merle's the kind of person who always puts Merle first!"
Obviously, the show by its very nature is known for its gore. But how do you keep those scenes different and find new ways to show the blood and guts? And can anything ever top that well scene from season two?
"The key there is hiring the best effects team in the business, and that's Greg Nicotero and his KNB EFX Group. Geniuses. Because these are characters that they're creating, and there is a backstory for each and every one of them, and I think that's what makes it different. They are individuals and in a way you almost have empathy for some of the zombies. That's another thing that I think is different and perhaps unique about this series."
I heard there are new animatronic zombies this season. What do they add to the show?
"Yes, we get to try something new, and that's certainly one thing that the team was working on during the break between seasons. There's only so much that you can do with a person in makeup, and with the CG zombies, if you got a close up the CG characters often still look CG. But if you have a puppeted animatronic head, you really can get a great deal of expression and it can do far more in a more believable way.
"You can also create characters that are clearly far more emaciated or missing vital parts that a human couldn't survive [without], so we couldn't cast an actor or an extra to play them."
If you had to pick one, what would you say is the theme for this season? We've heard lots about 'human menace'...
"The world really has been taken over by the zombies and humankind [has] to go to greater lengths and make more sacrifices to survive."
We've also heard that the season will be really fast-paced - would you agree with that?
"Yes, yes! But at the same time, you can't be so fast-paced that you lose out on character development. So there's going to be plenty of character development, but I think also everyone will agree that this season's scope is far larger than last season's."
So we'll be on the edge of our seats?
"I think so! We showed the first episode to the cast and crew last week, and of course they're a bit biased, but they were blown away. I came back from set last night and even though it's gruelling, obviously - we're halfway through shooting the season - people were so upbeat and enthusiastic."
I have to ask you about all those rumours going around about a spinoff movie. Is there any truth to those?
"It's certainly not something that's underway."
Is it something you'd be interested in in the future?
"You know, that's something that I defer to Robert Kirkman. As the creator, I defer to him."
What teases can you give us to get us excited about the new episodes?
"You really can't believe where we're going this season. Whatever you think you're going to see, I promise you we'll shock you and surprise you. It's a windy road! A very windy road."
It does sound exciting...
"Well, thank you! We love the fans that we have around the world. You probably know I'm on Twitter, and I've got a huge number of followers in the UK. It's so interesting seeing the number of people who are so passionate they're already counting the days, hours and minutes until it premieres on FX UK. It'll be here sooner than we think! There'll be as much drama as the Olympics!
"I was there for the last couple of days, I went to the closing ceremony, and it was fantastic. I felt that kind of heart-pounding drama where you're completely obsessed. I'm hoping that that's what our fans and viewers will think this season, which is that the next episode after they've seen one can't come fast enough."
The Walking Dead season three begins on FX in the UK on Friday, October 19 at 10pm. In the US, the series returns on October 14 on AMC.