There was a time, not too long ago, when blockbuster adaptations of Young Adult novels were all the rage at the box office. But, while Twilight and The Hunger Games were huge hits, later efforts like the Divergent and Maze Runner series flopped. However, Lord of the Rings director Peter Jackson is giving it another shot with Mortal Engines, a steampunk tale about scrappy youths and giant, mobile cities.

A teaser trailer for Mortal Engines debuted back in December before The Last Jedi, but that spot didn’t reveal much of the plot, other than that London is a big scary tank-city that tries to eat a smaller town. The first full trailer, released on Tuesday, offers up much more story.

Our heroes are a scarred assassin named Hester Shaw (Hera Hilmar) who finds herself a captive inside London after the giant mobile metropolis captures the town she was in. She has a purpose, though, and attempts to kill Thaddeus Valentine (Hugo Weaving), as he killed her mother and generally seems to be up to no good. A London resident, Tom Natsworthy (Robert Sheehan), gets wrapped up in Hester’s plot because he knows too much.

It looks like a fun little film, but the 2001 young adult novel it’s based off of is the first of four in a series. Between general YA fatigue and the knowledge that Jackson also turned The Hobbit into three bloated movies, Mortal Engines might be facing an uphill battle, especially if it’s intended to be a franchise-starter.

Mortal Engines opens on December 14, 2018.

Photos via Universal Pictures