How Groot turned over a new leaf
Old growth Just a twig Tree pose
Before he was everyone’s favorite talking space tree, Groot was something considerably darker. As in “the dark and terrifying woods.” Since his big-screen debut as the lovable, lumbering log in 2014’s “Guardians of the Galaxy,” he has been chopped down to size … and is back (and chipper) as Baby Groot, a sapling of his former self, in “Guardians of the Galaxy Vol. 2.”
Yet another Stan LeeJack Kirby creation, the character first appeared in “Tales to Astonish” No. 13 (1960), before any of Marvel’s Silver Age heroes had sprouted. He was originally an alien invader, capturing humans for experimentation. Gnarly. He didn’t return until 1976, when he and other monsters of that era of Marvel fought the not-so-jolly green giant Hulk in “The Incredible Hulk Annual” No. 5.
In 2006, Groot joined “Nick Fury’s Howling Commandos.” These were not your father’s World War II soldiers. These were good-guy monsters, including a werewolf named Warwolf.
Old Groot and New Groot were later retconned as separate entities when latter, nicer Groot, who joined the Guardians of the Galaxy, got his own title in 2015.
There’s also another origin story in which Groot turns out to be Puerto Rican. That is, stemming from Puerto Rican flora.
After Groot’s sacrifice at the end of the first “Guardians,” the movie’s tag scene showed a very much alive twig dancing in a pot. In the new movie, he has grown … a little.
“He really is just a sapling coming from the original Groot,” says visual effects supervisor Christopher Townsend. “We went through a lot of R&D, how to break the surface (of his skin) up, using the grain of the wood; how the veins move separately from the underlying skin.”
He says writer-director James Gunn “wanted him to be 10 inches tall, look like a baby and behave like a toddler. At the same time, we had to remember he was an alien tree creature, so nothing too anthropomorphic.
“We did some mo-cap (motion capture) tests using young children, 2-, 3-, 4-year-olds. But when we mo-capped that data onto the character, it looked like a 3-year-old dressed in a Baby Groot costume.”
After the toddler experiments failed, they chose to depict his movement mainly through “key-frame” animation (a technique closer to traditional animation). Key frame doesn’t use a human data reference — none of those dotted leotards. Instead, it defines certain movement targets. That is, a hand might be on a hip in one frame, and 10 frames later, in a pocket. Between those “key frames,” the computer fills in the hand and arm’s movement from hip to pocket. Just as James Gunn’s brother, Sean, appears not only as the Ravager known as Kraglin but also as the mo-cap reference for Rocket Raccoon, the writer-director turned out to have the best understanding of how Groot should groove.
Townsend says, “James would say, ‘He
should move like this,’ or ‘He should have an expression like this.’ So I would end up, just with my iPhone, filming him.”
For a dancing Groot sequence early in the new film, “I said to James, ‘Can we just film you doing the dance moves?’ So we used that as our base, in our previz world.”
Then, when they were ready to refine the scene, “We set up five cameras here on the Disney lot, and we shot him with the music. He acted it out with these crazy, silly dances.”
Townsend says Gunn warned, “‘Look, everyone’s going to think he’s ridiculously cute. We need to turn down the cute.’ We didn’t want him to be stylistically cutesy. James often referred to very flat performances — ‘Make him more Buster Keaton.’ He’s generally oblivious to a lot of things. When you look at a toddler, they’ll be staring up in the corner at a fly, something totally different.”
“Fast and Furious” star Vin Diesel had one of the best gigs in the Marvel Cinematic Universe, recording the signature line, “I am Groot,” for its dozen or so uses in the film.
“I think we had one day of ADR (dubbing) with him,” says Townsend. “He did lots of passes, lots of different readings; James would give him the direction. He was doing normal Groot voice, high-pitched voice, various things. Then in the sound mix, they modulated them to get the pitch they wanted.”
Townsend says “Vol. 2” was such a massive undertaking that it had 2,301 visual-effects shots. “I think there are 66 non-VFX shots. Because of that, we had to share the work among many companies.
“That opening title sequence when he’s dancing probably took about 14 months to do.”