While we still don't know when production will begin on the highly-anticipated adaptation Mortal Engines, which Peter Jackson is co-writing and producing, the cast is starting to come together, with Hugo Weaving signing on for an unspecified role. While it remains to be seen when the cast will be complete, Peter Jackson took to social media today, revealing the first piece of concept art from this fantasy adaptation. The concept art gives us our first glimpse at one of the massive cities at the forefront of this adaptation, plus one of the main characters.

Peter Jackson debuted this image on his Facebook page earlier today, although he didn't shed any light on what was being shown in this image from this fantasy adaptation. It appears that the character in the foreground of this image is one of the main characters, Hester Shaw, played by Hera Hilmar, who is seen looking at one of the massive wheeled cities this story centers around. In this desolate landscape, every major city is on wheels, moving around the Earth, looking for smaller towns to consume. While we don't actually get to see the wheels this massive city is on, the illustration does show different kinds of aircraft that are seen flying into the city.

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The cast also includes Robbie Sheehan, Ronan Raftery, Stephen Lang (Avatar), famed South Korean singer/actress Jihae, Leila George, Colin Salmon (Limitless), Patrick Malahide and Rege-Jean Page. It isn't clear quite yet how many more characters still need to be cast. It also hasn't been confirmed when production will begin quite yet, but Universal Pictures and Media Rights Capital has already set a December 14, 2018 release date. As of now, it will only go up against Sony's animated Spider-Man movie, but it will also arrive a week before Warner Bros.' Aquaman and two weeks before Disney's Mary Poppins Returns.

Set in a world many thousands of years in the future, Mortal Engines begins as Earth's cities now roam the globe on huge wheels, devouring each other in a struggle for ever diminishing resources. On one of these massive Traction Cities, Tom Natsworthy has an unexpected encounter with a mysterious young woman from the Outlands who will change the course of his life forever. Both Peter Jackson and Fran Walsh acquired the rights to this fantasy adventure series from Scholastic back in 2001, around the same time his first Lord of the Rings movie was hitting theaters.

While Peter Jackson and his longtime collaborators Fran Walsh and Philippa Boyens reunited to write the screenplay adaptation, Peter Jackson handed over the directorial reins to Christian Rivers for this Mortal Engines movie. Mortal Engines marks his feature directorial debut, although he has worked with Peter Jackson for 20 years, starting his career at Weta Digital as a digital artist on Contact. He worked in the visual effects departments on The Lord of the Rings trilogy, and on the first Hobbit movie, but he moved up to serve as a splinter unit director on the last two Hobbit movies, and also served as a second unit director on Disney's Pete's Dragon. Take a look at the concept art for Mortal Engines below.

Mortal Engines concept art