It’s been a quiet few years for New Zealand filmmaker Peter Jackson. After the director completed his (perhaps ill-advised) trilogy of movies based on the original The Hobbit novel, Jackson has mostly kept his focus on long-developing projects, including the sequel to 2011’s The Adventures of Tintin and his rumored adaptation of Philip Reeve’s beloved Predator Cities series. And earlier this week, Jackson shared a first look at some of the concept art from the latter film.

In the photo (via /Film), we see the mysterious scar-faced girl of Mortal Engines who, along with protagonist Tom Natsworthy, struggles to uncover the mystery at the heart of the film:

Peter Jackson

Here’s how Jackson described the futuristic book series in his original Facebook announcement:

They present a stunning look into the future, when all of Earth’s major cities are now mounted on wheels, roaming across the landscape as massive “Traction Cities.”

Our society has build itself on the principals of Municipal Darwinism — this basically involves the bigger cities hunting down, and consuming, the smaller ones. And that’s only the backdrop to an original and emotional personal story.

Having never read Mortal Engines or its follow-ups, I cannot speak to the quality of the books, but the image of giant roaming cities doing battle with each other is certainly striking (to say the least). Maybe a few years away from the day-in, day-out of filmmaking will help Jackson find his creative spark, too. The director has previously described feeling like he didn’t have “time to think” on the set of The Hobbit movies; spending a few years developing the idea before diving it will probably help Jackson return to the visual and creative storytelling that made him one of Hollywood’s most in-demand filmmakers for the better part of two decades.

The cast of Mortal Engines currently includes Hugo Weaving, Stephen Lang, Robert Sheehan, and Hera Hilmar. The film will hit theaters on December 14, 2018.