It's easy to forget that Vin Diesel lends his voice to everyone's favorite sentient alien tree Groot. But his role in the MCU wasn't the first time the actor headed to space in one of his films. His very first breakout role, after all, is owed to "Pitch Black," a blend of sci-fi and monster horror that first introduced us to Riddick. Eventually, two more films would follow, as well as an upcoming and highly anticipated fourth installment titled "Furya."

Apart from his gruff exterior, it's Riddick's night-vision eyes that end up being the most striking and captivating aspect of Diesel's character, adding an ominous beauty to an otherwise intimidating figure. But in order to create the effects of Riddick's eyes — a glimmer similar to the one replicant's display in "Blade Runner" — the actor had to suffer quite a bit behind the scenes.

Eye effects have always been notoriously uncomfortable. But not only were the ones that Diesel had to wear on the set of "Pitch Black" incredibly irritating to wear, they also ended up sending him to the hospital.

A Trip To The Hospital

In an interview with IGN, Diesel explained that throughout the filming of "Pitch Black," both contacts and CGI were used to give his eyes their effect. "If [my character] Riddick … turned a certain way," he said, "they would accent a moment in that sequence and punch up the effect a little bit — add a little light in the eyes." Diesel continued:

"For the most part, it was just contacts. The contacts were prototypes, they had never been tested or worn before. So it felt like — imagine going to your father's 1960 Plymouth, taking the hubcaps off, painting them blue and sticking them in your eyes. They had to fly out an optometrist from three hours away on the first day because they couldn't get 'em out. And they were like, 'What the–?' And at the end of that, I had to go to the hospital."

Luckily the prototypes didn't cause any permanent damage, just a scratch on his eye that was examined and apparently deemed as nothing to worry about. "It was a grueling experience having to wear those contacts," Diesel said.

But this begs the question of what the actor wore for the rest of "Pitch Black" and in subsequent films like "The Chronicles of Riddick." Turns out they needed to use CGI a bit more than Diesel might've liked for his Riddick trilogy after the failure of the prototype contacts. But that didn't stop him from wearing contacts in later films — which hopefully upgraded and improved versions of the ones he used on "Pitch Black."

Diesel Still Loves Using Contacts

By the time Diesel and director David Twohy reunited for a third time to film "Riddick," you'd think their need for uncomfortable contacts would've expired. But while speaking with First Showing, Twohy revealed that he actually leaned more towards CGI than contacts even during the filming of "Pitch Black." Ironically enough, the director also explained that Diesel continued to use contacts for Riddick's eyes long after his harrowing experience with them.

"In 'Pitch Black' we used contacts for certain medium shots. Long shots it didn't matter. Medium shots we got away with some contact lenses. But in all the close-ups it had to be CG. Sometimes we struggled with them. But you don't need contact lenses anymore. They were supposed to be early on tracking markers for his eyes. So you don't them anymore, but Vin insisted on having them anyway because it's kind of a rite of passage with him to put them in. He would put them in on special days, like maybe the first time that Karl Urban showed up on the set. In special moments, he'll actually go to the length of putting in the mirrored contact lenses, knowing that we're going to paint over them, knowing that we're just going to CG right over them. But he wants to do it for him and the actor he's playing against."

Rite of passage or not, it at least makes sense why the actor would want to wear them for his costars like Karl Urban. Little effects can go a long way to immersing everyone into the world of the film. Especially when it comes to something like Riddick's eyes, which are supposed to be incredibly striking and the first thing you notice about the character.

How Not Being Able To See Helped Riddick Feel More Real

Diesel's commitment to Riddick is pretty self-evident in his willingness to put his eyes through further agony. But the contacts served another purpose in his eyes — pun very much intended. "As an actor, you rely so heavily on your eyes," Diesel told IGN. This pushed the actor to find alternative methods of expressing the inner thoughts and motivations of Riddick.

"Your eyes are a great sort of resource for communication of thoughts and emotion, and you're stripped of that, you have to use other things you haven't used before. You develop mannerisms, and you really rely on creating that inner emotion and hoping that comes through. And the contacts did that, the goggles did that. I think a large decision was made in creating this character in terms of the process and that was to rely on not showing his emotion and hoping that somehow showed his emotions, that that would somehow give you an idea of what's going on."

Diesel brings up a good point that, even without the contacts, he'd still have been pretty hidden behind those welding goggles. To anyone else, the role of Riddick might've been limiting, painful, and would've come off stiff. But Diesel manages to find those other forms of non-verbal communication that make Riddick more than just a beefed-up antihero. Like a space-questing Mad Max, he subtly displays a silent intellect that aids him and those around him in escaping various blood-thirsty alien creatures.

With a fourth film on the way, one can only hope that at the very least whatever contacts Diesel decides to wear for "Furya" will be his most comfortable pair to date.

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The post Vin Diesel's Pitch Black Contact Lenses Were A Punishing Costume Choice appeared first on /Film.