This prequel to the Mortal Engines quartet occurs before traction cities and before Municipal Darwinism.
In a teasingly recognisable London threatened by northern invaders, orphan Engineer, Fever Crumb, is assigned to help renegade archaeologist Kit Solent.
They unearth not only artefacts, but also a disturbing link between Fever and city founder, Auric Godshawk and secrets about her guardian, Dr Gideon Crumb, that will change her life - and this world's history.
This is vintage Reeve; Fever is a wonderfully doughty heroine, the other characters have a Dickensian exuberance, (there's the wildest sedan-chair chase ever!) and the steam-driven plot powers along.
London is portrayed with enormous wit and there are moments of spine-tingling recognition of the saga yet to unfold.
Fantastic, nail-biting stuff!