Director Guillermo del Toro (L) Poses With Cast Member Charlie Hunnam At The Premiere Of 'Pacific Rim' At Dolby Theatre In Hollywood
IN PHOTO: Director Guillermo del Toro (L) poses with cast member Charlie Hunnam at the premiere of "Pacific Rim" at Dolby theatre in Hollywood, California July 9, 2013. The movie opens in the U.S. on July 12. REUTERS/Mario Anzuoni

"Pacific Rim 2" is still three years away from its U.S. release on April 7, 2017. However, director Guillermo del Toro has already revealed some of its plot details inlcuding which characters are set to return and how different the Kaijus are in the sequel.

So what is to be expected from the sequel and which Kaijus will be featured next? In his previous interview with Collider, movie director Guillermo del Toro talked about the first draft for "Pacific Rim 2" having been turned in already. He said it would be four to five months on the screenplay before the start of pre-production. He also added that the sequel will be a very different experience since not all of the viewers' favourite characters are coming back.

Now in his recent interview with Collider, the director further revealed that among the many main actors, only Charlie Day and Burn Gorman are set to return. The two actors will reprise their role as Dr. Hermann Gottlieb and Dr. Newton Geiszler, respectively. "They are really, really - I mean, honestly, they are probably the guys I have the most fun writing along with Hannibal Chau so just from a purely selfish drive, I like writing them," he said.

So what happens to Jaeger pilots like Raleigh (Charlie Hunnam) and Mako (Rinko Kikuchi)? Guillermo didn't confirm their return but he reportedly hinted their involvement in "Pacific Rim 2." The sequel will eventually need the help of the Jaegers at some point since the sequel will supposedly feature new Kaijus. Additionally, in his previous interview, he hinted of other characters' return. Hoping for "Pacific Rim" to be a trilogy, del Toro said, "some characters come in at the end of the second, hoping that it will ramp up on the third one."

On the subject of Kaijus, del Toro told Collider that the robots will be "very different." The sequel will reportedly feature different types of Kaijus. However, their existence in the sequel will not be immediately felt since the "Pacific Rim 2" timeline starts a few years after the first one.

"It is the world having been freed of Kaiju, what happens to the world after - what happens to the Jaeger technology once the Kaiju are not a threat. It's quite a jump," he revealed.

Perfecting the "very different" Kaijus' appearance in the sequel apparently needs a lot of time, and producers are not delaying any movie productions. Guillermo del Toro said in his previous interview with Collider that pre-production for "Pacific Rim 2" starts in August to September next year, then they get a month of rest before filming starts in November to December.