Sometimes, you read the description of a book and say to yourself “I have no idea if I’m going to like this or not, but I absolutely need to know for sure.”

That was where I came down on Daniel H. Wilson’s new book “The Clockwork Dynasty” (Doubleday, $26.95) when I first read about it. Wilson is best known for the best-selling “Robopocalypse,” but this new offering looked like a bit of a genre departure.

History marks a period when the notion of automata - mechanical men and women that could be made to act real through elaborate machination using springs, clockwork and the like – was very big in the courts of Europe. Rulers from all over the world were fascinated by these meticulously-constructed devices that mimicked human behavior.

But what if they could do more than just mimic.

“The Clockwork Dynasty” tells the story of a group of automata – they call themselves “the long-lived” or the “Avtomat” – that have been operating in the shadows behind human history for centuries. They are driven by their anima, a sort of soul that gives them both consciousness and purpose.

Peter is one such being. He awakes in the workshop of a mechanician serving the Russian ruler Peter the Great in the early 18th century. His anima – his Word – is “Pravda,” or justice. Along with his sister Elena – a child-shaped being of vast intellect steered by logic – he serves his master, whose plan is to install his clockwork namesake on the throne following his demise, thus ensuring his name shall live forever. This plan goes awry, however, with Peter and Elena forced to flee into a world from which they must hide their true nature.

In the present day, June is a scientist/historian specializing in the nature of these automatons, relics of a moment in time; her interest springs from strange battlefield stories and an odd keepsake courtesy of her grandfather.

But when one particular investigation goes too deep, June finds herself in the middle of the centuries-old battle amongst the long-lived. See, the power is running out. And there’s no one left alive who knows how to fix it. The only choice – steal life from your fellow Avtomat.

Circumstances dictate that June joins forces with Peter, whose largest struggle is to find the right way to be true to his purpose. Unfortunately, justice isn’t always so easy to find when you’re fighting for your very existence.

It’s a battle between factions that know each other like family – a battle that can ultimately have only one victor. The Avtomat have long been hidden from humanity, but desperation have forced them out of the shadows for a final confrontation.

“The Clockwork Dynasty” is a lot of things. It has a steampunk sensibility. There are elements of both science fiction and fantasy at work. There’s even a whiff of historical fiction. Plus there’s some deep-down conspiracy thriller stuff.

It’s a lot – but it works.

The idea of others operating behind the scenes of history isn’t a new one for speculative fiction. We’ve seen all manner of stories told about aliens and/or monsters pulling the strings from the shadows. But Wilson has approached the idea from a new place, lending the situation a freshness that it might not otherwise have had.

The richness of the world-building comes through in the alternating narrative timelines. The story moves between the present and various touchstone points in Peter’s past, allowing for a welcome degree of storytelling flexibility. Each timeline allows Wilson the opportunity to more fully develop this intricate universe through details and expanded context.

Of course, the propulsive nature of the story is what really makes “A Clockwork Dynasty” tick. Without that, all the world-building in the … world … won’t save you. But Wilson has a great knack for pace and engaging action; it’s a book that is very difficult to put down.

It’s an exceptional piece of speculative fiction, set in a world that I would very much like to visit again. Steampunk and other genre fiction fans should give it a whirl.