Rachel Caine's 'The Great Library' series is now done, but Genevieve Cogman marches on with 'The Invisible Library' series and, frankly, it's easily as much fun as it's ever been. While I would like to read something different by this talented author whose prose is getting smoother with every new book, I also hope this series continues on as long as she wants to write it.

What's new this time out in book six is that the truce that was being sought in 'The Mortal Word' has been signed. The dragons, the fae and the Library have agreed terms and the truce is applying on a grand scale. This means a major caveat to business as usual. Librarians can't steal books from either dragons or fae, or the worlds that they've claimed, if they've signed up to the treaty. That's going to make life tough in the future, I'm sure.

I also mention it here because, as with that book, this one is quick to keep on progressing a grand multi-book story arc, the little detail of a new book that needs to be stolen very much serving the bigger picture. That's no bad thing, as Cogman is successfully keeping this series from moving into theft-of-the-week territory. There's a book to obtain here, but that book is more of a teasing spark than the main conflagration.

In particular, Irene is tasked with obtaining a singular copy of an Egyptian text called The Tale of the Shipwrecked Sailor, as it will serve to counter the chaos that's taking over the world on which she went to school. However, it's not a theft this time. She's sent to its current owner to negotiate a trade and the terms that emerge for that trade prompt the theft: she'll get the book in return for playing her part in a major art heist.

And that heist comprises the bulk of this book. It's fascinating not only on its own merits but because the team Irene has to work with is a rather mixed affair, so much so that cooperation between its members is far from a given. Irene and Kai are an odd enough team to begin with, being a Librarian and a dragon respectively, but Indigo, their hacker, is a dragon too (and one who Kai instantly recognises and despises) while Ernst (muscle), Tina (driver), Jerome (gambler) and Felix (thief) are all fae. Oh yeah, this is going to be interesting!

I should add, not because it's particularly important but because it sets it all into motion, that the man who put this team together, known mysteriously as Mr. Nemo, is a glorious character, as befits the fantastic series concept that fae don't so much live lives as play parts in their own stories. While that immediately set up the potential for crazy plot conveniences, I've been happy with how Cogman has explored the idea over quite a few books.

Nemo's part is arch-villain and he lives up that very well indeed, inviting the crew for his heist to his partially undersea lair on his private island in the Caribbean. He literally feeds an enemy to the fishes, sharks in this instance. He issues his instructions over videoscreen and sets up the heist over dinner, feeding his guests liver of great white shark and fugu sashimi. It's all exquisitely delicious and I'm not only talking about the dangerous meal.

The job, as outlined, is to steal Géricault's The Raft of the Medusa from a museum, which on the world in question is in Vienna rather than Paris. Hey, the last book was set in Paris and I'm sure Cogman is enjoying sending these characters on a virtual Grand Tour of alternate worlds. Hilariously, one of the consequences of so few details being provided is that nobody in the crew realises until they're on the job that this is a frickin' huge piece of art! You just can't slip a painting under your shirt and waltz out with it when it measures twenty-three feet by sixteen.

Of course, if it was going to be simple, it wouldn't take an entire novel to unfold. The crew have to battle the logistics of the operation, as well as each other because trust is not high, while dealing with an oddly dystopian authority called CENSOR, the apparent presence of supernatural entities on a supposedly high-order world and the fact that there are dragons here too, on a world unclaimed by either side. Quite obviously, there's more going on in this Vienna and with this heist than the crew are aware of finding out what is a good part of the fun.

As I understand it, 'The Invisible Library' books were initially bought as a trilogy and published by Roc. Ace then bought the next two books, extending it into a series, which they're apparently more than happy to continue. This is a sixth episode and Cogman is working on a seventh.

I can understand some of what Roc might have gone through. I liked the first book but had a number of reservations about some of what it did and that ran on into the next two. However, since Ace picked it up, it's felt smooth and easy and delightful. I don't know how much of that is Cogman getting better and more comfortable as a writer and how much is a different editor working with her but, wherever the praise should go, I'm throwing out more with each book that the author conjures up.

With a quick grin for a neat Brexit joke snuck into the text, I'll wrap with the suggestion note that I'm really liking where the bigger picture seems to be taking us. One of the best things Cogman has done over the last couple of volumes is to take the well-defined boundaries that she set early and, well, blur them a little in believable ways. This deepens the worldbuilding in my view and sets up a wild range of possibilities for where we're going next. ~~ Hal C F Astell

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