Sons of Anarchy star Charlie Hunnam has become the first actor to join the cast of Pacific Rim for director Guillermo del Toro.

Travis Beacham wrote the screenplay, which centers on these enormous creatures called Kaiju, who emerge from the ocean and set out to destroy Earth, one city at a time. The humans must develop a new brand of weaponry to ward off these evil beasts. It isn't known what role Charlie Hunnam will play yet.

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Back in March, we reported that Guillermo del Toro is rewriting Pacific Rim, so that no attacks will take place in Japan. The rewrite comes in the wake of a massive earthquake which rocked the island country, claiming over 10,000 lives in March.

It still isn't clear when production will start on Pacific Rim quite yet.