Watch James Gunn Explain How 'Guardians of the Galaxy' Made Dancing Baby Groot

Guardians of the Galaxy is the biggest movie of the year thanks in part to a monosyllabic, walking tree.

Groot, an animated being ostensibly made of alien wood, provided the heart for the ragtag team of cosmic superheroes, and as writer-director James Gunn told Yahoo Movies this week, it was the voice actor Vin Diesel who provided the heart for Groot.

“Vin had a strange attachment to Groot. First of all, it’s not a secret, he was going through a very difficult time in his life when the character came to him, and he just felt like it was a big relief to just get into something very simple,” Gunn explained, alluding to the death of Diesel’s Fast and Furious co-star Paul Walker. “It was a character he was able to share with his children, who were very young, and had never been able to see one of his movies in the theater. And he was able to just tune into this character in a very simple way and find this spiritual center. I don’t think that goes unnoticed in the character in the movie.”

The one variation in Groot’s signature line comes at the climax of the movie, when he seemingly sacrifices himself to save Star-Lord, Rocket, Gamora, and Drax. As we know though, you can’t keep a good Groot down, and in the above extra from the Blu-ray (out Dec. 9), Gunn explains how they designed the Baby Groot that everyone loves so much.

Gunn spoke with Yahoo Movies about the dancing seedling and other matters of extreme importance.

Is Groot invincible as long as he gets stuck in water?
That’s an unanswered question: Is Baby Groot, Groot? Or is Baby Groot actually Groot’s progeny?

Wow, like how if a nut falls off a tree and then its seed eventually grows a new tree, those are two different trees?
Exactly. It may be answered in the future, but that’s the question.

So does Groot look exactly the same when he grows up again, or is each Groot iteration, like a snowflake, unique?
You’ll have to wait and see until it gets big! He’s still a baby right now.

The talking tree in your movie has inspired a lot of philosophical questions.
It comes from Vin Diesel’s philosophical approach to doing the character, I think.

You animate things before the voice comes in, but were there tweaks to the Groot animation once he did the voice work?
Oh yeah, for sure. We shot Vin with all the dialogue, just like we shot Bradley with Rocket and we shot my brother with Rocket, and that stuff was used. And we shot me for doing certain things for Groot. That was the way we developed the character, in part using those human references.

You were the dancing model for Baby Groot. Were there any animation moments that you had to provide your body for?
Yeah, a lot, at the beginning of the movie especially when we were designing Groot’s walk, because Groot is sort of this amazing slacker, which isn’t brought up much. But he is really lazy in comparison to the other Guardians of the galaxy, and he’s got this very slow slacker pace and he’s always lagging behind and he’s always looking at something other than what somebody is talking about. I don’t think Groot is involved in 90 percent of the conversations that the Guardians have, because he’s always looking and thinking about something else.

And so when we were originally doing the movement test of Groot, of how he moved, and also how he would sit down and his branches would become a part of the chair, and he’d stand up and break away from that, that was all stuff that I shot early on, both in a [motion-capture] suit and just me.

Rocket is an animal, but really has a human mind with his modified human brain. But with Groot… The question is always: Goofy is the human dog and Pluto is dog dog. So is Groot a human tree or a plant tree?
I think he’s an alien life form that is very different from what we are, and to say he’s an animal or a human, both of those things would diminish the importance of what a Groot is.

Are there other Groots?
There may be! There might be! Who knows?

Marvel just laid out a huge slate of movies over the next few years. How much are you part of the discussion when it comes to planning those movies, and how much do they impact Guardians sequels?
I actually try to keep Guardians as much its own thing as possible, and they’ve been pretty behind that. I think with the success of the movie, it has made it that Guardians is more the cosmic wing of things. There will be moments where they’ll intersect, but for the most part, it’s not about the Guardians and the Avengers teaming up. That doesn’t interest me. We don’t want to be subservient to The Avengers — I think we’re equal to the Avengers.

Do you think there will be spinoff movies for the Guardians characters?
Yeah, I hope so. I think there’s lots of interesting characters in the movie, some of them are Guardians and some of them aren’t.

Which non-Guardian would be interesting to you?
I really love Yondu and Kraglin, the Ravagers. I also love Nebula quite a bit, I think they’re all really interesting characters. Yondu got a bit of play in the first movie, but Nebula I think has a lot more to offer that we haven’t quite seen yet.

When you’re writing a movie, do you think about the sequel and a third one?
I don’t think of it so much in a linear fashion; I think of it more as a starburst, like where do all of these characters go from here? What do they do? What happens to them? Are there ways we can tell those stories through another medium, whether it’s film, television, comics? How can we tell more stories about characters on the cosmic side of the universe?

Are there characters that you’d like to get in the from the cosmic side that we haven’t seen in Guardians?
Oh yeah, definitely, we’ll even see in 2 hopefully — we have a few characters that I really am fond of that we’ll bring into the universe.

When do you go to production?
We don’t have a schedule yet. The only schedule we have is we know that we’re coming out in May of 2017.

Before Guardians, you were an indie director. Do you plan on doing anything in between, like Joss Whedon making a little Shakespeare movie in between Avengers movies?
No, I have no interest in that. Guardians takes a lot of work. I mean, you have to create entire cultures and worlds and planets. And frankly, with the first movie, I had two years to do it, and I did not feel like it was enough time. 

So, by the time of the next movie, will we see adult Groot again?
I think you’ll have to wait and see for that.

Related: Here’s That Clip of Dancing Baby Groot in All its Galactic Glory