Infernal Devices (Mortal Engines, Book 3)

In Mortal Engines, the once-mobile city of Anchorage has settled into a static existence on the remnants of America. Tom Natsworthy and Hester Shaw enjoy their newfound safety, but their adventurous daughter, Wren, is irresistibly drawn to the call of the unknown. When a charismatic submarine pirate offers her an escape, she seizes the chance, unaware that her mission to steal the enigmatic Tin Book will spark a conflict with world-altering consequences.