'Pacific Rim's' Guillermo del Toro on Box-Office Pressure, Planning a Sequel (Video)

Pacific Rim will bring to the big screen a collection of larger-than-life monsters and robots who go to battle over Earth.

But while these breathtaking creatures and creations may seem like they come simply from the wild imagination of director Guillermo del Toro and his co-writer, Travis Beacham, they are actually based on real-life creatures and machines.

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"We tried to reference real animals," del Toro tells The Hollywood Reporter of the monsters, called Kaiju, which resemble giant cousins of amphibians, reptiles and sea life that roam the Earth today.

"We created a silhouette or a shape that defines their function. Then we filled them with details that are real, natural -- that's what I call the National Geographic approach."

In del Toro's tentpole, in order to fight against the giant monsters that have invaded Earth, humans have created huge robots that take two pilots to navigate. The Warner Bros. and Legendary film stars Charlie Hunnam, Idris Elba, Rinko Kikuchi, Charlie Day and Ron Perlman.

Del Toro approached the design of these massive robots in the same way he created the monsters -- he based it on real life.

"We tried to base them on real machines -- submarines, nuclear reactors, ships, World War II bombardiers," he says.

For example, Gypsy Danger, the robot piloted by Hunnam's character, is based on the Empire State Building, the Chrysler Building and John Wayne.

"These are things that are not coming from any other cinematic references," del Toro adds.

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Pacific Rim will hit theaters July 12, but the film already has been under a microscope for how it will fare at the box office. Del Toro, who helmed Hellboy and Pan's Labyrinth, tells THR that he has done his part of the process to the best of his ability.

"I can only make the movies," he says, "and know that I am in the hands of the best marketing team in the world and come here, do the promotion, talk to the fans and keep going."

But even though del Toro's film hasn't hit theaters yet, he says he's already been batting around ideas for a sequel.

"We started thinking about a sequel when we got a great response from the first cut that we showed to an audience," he says. "We have plans that are pretty bold and pretty crazy. We would not be repeating anything from the first one. We would go to completely fresh territory."

Pacific Rim opens in theaters Friday.

Watch THR's interview with del Toro above.

E-mail: Rebecca.Ford@THR.com
Twitter: @Beccamford