The best animated movies are the ones that tackle adult themes that belie pure children's entertainment: the fate of Bambi's mother, Mufasa in The Lion King, Carl's wife in Up. Grief and loss are more ingrained in our childhood favorites than they are in most R-rated movies we see today. (John Wick excepting.)

And while the first How to Train Your Dragon film in 2010 didn't dive headfirst into trauma, nor did it skirt around the issue. We began the films with Hiccup (voiced by Jay Baruchel) as a gawky teen in a Viking village whose fondness for dragons make him a reluctant heir to his father, the village Chieftain, Stoick (Gerald Butler). After bonding with a crippled dragon named Toothless, Hiccup is forced to adapt to brutal realities:  in the first film, he loses his leg; in the sequel, his father.

How to Train Your Dragon 3: The Hidden World approaches the idea of loss very differently as Toothless meets a potential mate and discovers a new world that is free from the human threat. Sometimes a loss isn't something being taken from you, it's something you learn to let go of. It's a tough theme, and one that the trilogy's director and writer Dean DeBlois has been grappling with as he closes the book on his part in the franchise.

We sat down with Dean two weeks before the premiere of the film to discuss working with famed cinematographer Roger Deakins, the franchise's dragon-identifying fans and his bittersweet farewell to the world of Toothless and Hiccup.

Collider: This movie was just stunning to look at it. What was it like working again with Roger Deakins as a visual consultant?

how-to-train-your-dragon-hidden-world-dean-debois
Image via DreamWorks Animation

DeBLOIS: It was so great. He's such a soft-spoken and mild-mannered guy but so full of wisdom, it's like a Masterclass every time he spends time with us. He's been working remotely, but when he is in town he'll spend an entire day and meet with every department. Once again, he was involved with every department, creating these mood boards of photo references; everything from a sense of mist or atmosphere to pallets. Then working with the camera department in setting up shots and talking about combining some, different perspectives...then all the way through to the end, working with our production designer and visual effects designer to fine-tune the lighting and make sure every sequence has a strong identity.

Collider: What is the development process like from conception to screen for animation? Do you imagine these – like that of the hidden world in– your head and try to explain them to the storyboarders? Are you ever surprised by the final cut?

DeBLOIS: Everything is an embellishment, so we'll start conceptually. From the writer point of view, I'll sit down with the production designer and say "Here's what I've imagined, here's its story's function," but that will set his brain on fire and he'll come back with all these ideas we'll discuss.

Like for the actual hidden world, I told him about a dream I had, of a hole in the sea. We started talking about it, and we're like "Okay, conceivably that could be an undersea volcano." That it was this doorway to the hidden world you could only access if you're on a dragon because otherwise, you'd sail right off. And that doorway might open up to tunnels and chambers. They might have bio-luminescent fungi and this salty, damp atmosphere where coral might grow in mid-air. It just keeps expanding.

Then the production designer and his art department might start doing paintings, so we get of what it's going to be. But when you see the final images and all the subtlety of lighting, it inevitably is something more than I could have dreamed up.

Collider: What were the biggest changes made during the production? There was a Drago B-story that got cut. Anything else?

how-to-train-your-dragon-3-the-hidden-world-poster

DeBLOIS: Ah yes, Drago was the villain of the second movie, who was going to have another facet of his personality...he was going to show himself to be multi-dimensional in this story. It wasn't even a B-story, it was a C-story, and the time it would have been needed to really care and feed that story-line to make it convincing and credible would have detracted too much from our limited screen-time that was devoted to Hiccup and Toothless' story. So it was abandoned as an idea, but that was maybe one of the bigger changes.

Collider: Let's talk about the villain in this story. Grimmel (played by F. Murray Abraham), has a line early on about how dragons are all thieves and murderers. How the word should never get out that we should think of them as equal. That language sounds very familiar after these last couple of years. Does Grimmel represent any commentary, political or otherwise?

DeBLOIS: He is definitely reflective of our times. He's elitist and very staunch and firm in his beliefs. He's very immovable. Hiccup is all about evolving and being inclusive, figuring out how to get along. Just as a base nemesis to that philosophy, Grimmel is just going to try to eradicate anything that brings that idea into this world.

Collider: And yet he uses dragons as well, which seems like a base sort of hypocrisy.

DeBLOIS: Right, right. I think even him just calling them murderers. They're not just killers...dragons don't kill to survive. He acknowledges them as sentient beings.

Collider: Going back to what you said about multi-faceted characters, I know that you outted Gobber–Craig Ferguson's character–after a line or two in the last movie. I think that makes Gobber the first confirmed gay character in a mainstream animated film.

DeBLOIS: Actually, I think ParaNorman came out before us, and there's a character who comes out at the end of that one.

Collider: Craig was telling me that he had essentially improvised that line, and that afterward you two had a discussion about it. How much did that go into how you wrote Gobber for this film?

DeBLOIS: I think it was as important to me to normalize him. I'm a gay man...I'm not out and loud and proud everywhere I go, declaring myself gay. It's part of who I am, and okay, I go about the rest of my life. I thought it was a nice bit of character enrichment to have Gobber come out in Craig Ferguson's little ab-lib, and beyond that, he's still the wise-cracking uncle type whose full of bad advise and always in there with an opinion. I love that primarily about his character. So there are little playful hints here and there, but it's not anything that was going to be an agenda.

Collider: The fandom for How to Train Your Dragon online is pretty intense. I'm not sure how much of it you check out yourself: the Tumblr, slash-fiction and fan art communities. It's obviously struck a chord with adults as well as children. Is that something you keep in mind when creating these films?

how-to-train-your-dragon-3-image
Image via DreamWorks Animation

DeBLOIS: I am aware of it, and most of the people here working on the film are aware of it because it's a very passionate and very outspoken group and they hold us to a certain standard because of their love of the characters and the world. I think we want to do right by them. A lot of decisions we question amongst ourselves, just to make sure we are not going to hopefully disappoint or enrage our fans by doing something that feels out of character.

Collider: Why do you think Hiccup and Toothless connect so strongly to adults as well as children. I was in high school when Lilo & Stitch came out, and I love that franchise, but I'm not first in line whenever there's a new animated film about magical creatures. Yet you've developed a fan-base of people who definitely are. Any thoughts on that?

DeBLOIS: I wonder the same thing. I think our character in particular–and this is going all the way back to Mulan, but also in Lilo & Stitch and the Dragon movies–there's a deliberate attempt to reflect ourselves: our insecurities and our little moments of victory. There are complicated people, and we try to make our characters complicated. Maybe that's what people see. I think everyone likes an underdog character that doesn't quite fit in.

Collider: Well, I think everyone likes an animal familiar. Especially one that reminds them of their best dog ever.

DeBLOIS: Yes, yes and yes. A powerful, loyal and affectionate pet. Some sort of friend. I grew up as a kid who didn't have a dog or a cat, and I wish I had a horse, so there's always this immediate love of animals that I have, and we've always wanted to imbue as many familiar traits into Toothless and the other dragons as possible.

how-to-train-your-dragon-3-hidden-animation
Image via Dreamworks Animation

Collider: In this one especially, even though the dragons don't talk, it feels like the ending gives more of a sense of personal will and freedom to the dragon community. It's sort of bittersweet. Instead of training them, it's about respecting them as equals and allowing them to make their own decisions. How did you feel about the ending of the film, and do you think it closes the book on any future sequels?

DeBLOIS: The end of the movie was a goal of mine realized. It was always going to be tricky because of the fan-base you're talking about, I didn't want to enrage or disappoint the audience, and we stood the chance of doing that by separating our star couple. If we didn't do it carefully and bring the audience along, they might resent us for it.

But to me, my favorite movies are the ones with the bittersweet endings. They're stories of disparate characters that come together, that affect one another's lives in really profound ways, and if they separate, they'll never be the same again. Elliot is never going to be the same kid after having met E.T. Harold is never going to be the same kid after having spent time with Maude. These stories have such a rich tradition, and I hoped we could contribute to that in our own way.

Collider: One question you have probably gotten a lot of today: Would you like to live in a world with dragons? If so, would you like to stay a human or be a dragon?

DeBLOIS: Living in a world with dragons, of course! What an amazing experience it would be, to climb onto the back of a dragon, some living breathing beast that could take wing and take you up to the clouds? Just the dramatic excitement of that would be unbelievable. And that's the experience we wanted to get audiences as close to as possible with this movie, almost putting them on the back of a dragon. Almost feeling your stomach rise up to the back of your throat as they dive towards the water. It's nice to be able to do it in a cinema, but man, to be able to do it for real?

Collider: The movie's ending does involve a separation. Are you leaving the door open to any sequels?

how-to-train-your-dragon-3-images
Image via DreamWorks Animation

DeBLOIS: For me, this is done. I don't own the franchise, so I can't promise there will never be another dragon movie out there. But I would hope that if they did decide to reopen it, they would go to a completely different timeline and completely different characters because, for me, the Toothless and Hiccup story is concluded.

And isn't it better to end after these three movies, and have people out there who wish there were more than have it go on forever and have people lose interest? I think ending it with integrity is better than letting it go on and on and on.

Collider: Well, it will always live on in the hearts of the HTTYD fandom community, of which, again, there are legion.

DeBLOIS: It's great. I am getting to know the fandom community little by little. But I wonder if all these animated franchises have such fervent groups out there.

Collider: When I asked on various social media platforms if anyone had questions for you, I got replies back from people who had HTTYD photos as their avatars, who identified with dragon fursonas, who had their own dragon pronouns. It was quite the rabbit hole to go down.

DeBLOIS: I've met a few of them. It's weird because this is such an insular community. We're making a movie we want to see and that we're proud of. We have no idea of how the world is going to react. When you realize after the fact–as when working on a sequel or in this case a trilogy– that with it comes great responsibility. You see how important these characters and stories are to some people, how connected they become. And for whatever reason, there are certain people out there who form a much deeper bond then we even have. It's a major part of some people's lives.

how-to-train-your-dragon-3-bluray-review
Image via DreamWorks Animation
how-to-train-your-dragon-3-image-toothless
Image via DreamWorks Animation