Getting a voice to sound just right for a film can be more difficult than you’d think.

When scouting for potential actors, casting directors will often pay just as close attention to the actor’s voice as his or her physical presence, mannerisms, and vibe. Quite simply, if the voice doesn’t sound right, the actor might not be a good fit.

Then you have voice changes within movies themselves.

Christian Bale’s ‘Dark Knight’

Remember Christian Bale’s frequently panned batman voice? The gruff one that sounded like a scratched record? Some fans complained that his voice broke their immersion because, in their opinion, it sounded too goofy. Tom Hardy and the production staff for Venom faced a similar dilemma: how to make Venom sound alien and also like Tom Hardy at the same time while still being believable?

After all, the titular “Venom” anti-hero is a parasitic symbiote that needs Tom Hardy’s body to survive. Venom is the result of the symbiotic relationship between Tom Hardy’s Eddie Brock and the alien life form. A splice of alien and human, and one that had to combine voice traits that the audiences expect for both.

In case your unfamiliar, Tom Hardy played investigative journalist Eddie Brock in “Venom.” Brock stumbles across an alien life form, a symbiote, that must bond with an oxygen breathing host in order to survive on Earth. The symbiote and Brock combine to create “Venom”, a powerful humanoid alien life form.

Tom Hardy’s ‘Venom’

Spiderman

Hardy also portrayed Venom. Yet simply using Hardy’s voice for Venom would have sounded, quite frankly, silly, and would have made it harder for viewers to suspend their disbelief. For movies, this is a big deal because if audiences are pulled out of the film, they are less likely to enjoy it and more likely to become critical.

The solution was to take Hardy’s voice and then process it to sound more alien. This might sound simple, but in production, it’s actually a bit tricky to pull off. Not only does the sound team have to make the voice sound human and alien, but the set team has to keep all the actors on track and focused. Green screens can be hard enough to act in front of. Mismatching and unheard voices can make things even more difficult. Ultimately the amount of technical work that goes into all this can be back straining. That’s why Hardy gave props to the “sound boys”, saying:

“It was really, really good fun, and the sound boys, actually, to be fair, probably really play Venom. ”

This highlights just how important all the set and technical work is  when bringing a movie and its characters to life. We viewers rarely get to scratch more than the surface, watching our favorite actors ply their trade. Yet the bulk of the work is actually happening behind the scenes, managed by sound technicians, stage crews, and technical consultants.

You rarely hear about them, but technical consultants are a big part of the movie industry. Consider Sony’s “Steve Jobs” film, they turned to none other than Steve Wozniak to provide insight. Remember Eddie Murphy’s classic “Nutty Professor” films? They roped in a genuine UCLA professor, Wayne Grody, to design the labs and provide technical insight.

Hearing Is…Believing?

Or how about the more recent Venom film? This time around, Walter O’Brien, the mind behind CBS’s hit show “Scorpion” was on stage to make sure everything was technically believable. In case your unfamiliar, Walter O’Brien is the real-life inspiration for “Scorpion”, CBS’s hit show that is based on O’Brien’s efforts to combat cybersecurity attacks across the globe. True to form, “Venom” hit October box-office records.

For “Venom”, O’Brien’s chief goal was to keep things believable. It’s hard to keep audiences plugged in when aliens, weird lifeforms, and everything else are mixing up on Earth. Most sci-fi flicks take it off-world to avoid these conflicts, but Venom brings em right home. This might seem like a minor detail, but making alien voices, weapons, technologies, and all the rest more believable on Earth takes a lot of subtly. That’s why Sony turned to Walter O’Brien to make Venom believable.