What if a librarian with a conscience, an archdemon with an agenda and a pair of short-tempered angels with a superiority complex all wanted to lay hands on the same book? Welcome to Hell’s Library.

Not every afterlife has a library (Heaven, for example. The logic is searing, but irrefutable). Hell’s Library is adjacent to the infernal realm, not subservient to it – and the Librarian of its Unwritten Wing is traditionally a human soul, because you can’t trust a demon with the dreams of humanity. In a world where souls choose the fate they feel they deserve, Claire Hadley is atoning for her perceived sins by protecting the unfinished stories dozing within its stacks.

But untold tales get restless. From time to time, one materialises as a character and tries to escape. When a wayward fantasy hero gets out without raising an alarm, Claire seeks to retrieve it before it causes any damage (because being confronted or seduced by your unwritten works can be confusing – even harmful – for an author). Along the way, she finds herself caught between Heaven and a book so powerful that Lucifer once purged Hell to keep its secrets. It’s not really a Librarian of the Unwritten Wing’s duty to protect a finished tome – but Claire is determined to protect humanity from the conflict brewing between Heaven and Hell.

Honestly, if that set-up doesn’t already have you screaming for a copy, just shuffle right along. AJ Hackwith has brewed a bubbly potion of delights that few bookworms will be able to resist, but if the concept hasn’t convinced you I rather doubt anything I can say about her peerless execution will make a difference.

This is a book I’ve been dying to read ever since I heard it pitched at Worldcon, and it was worth the wait. It’s a wry fantasy about the relationship between a book and its author, affectionately aware of the ways in which a story can get influenced, muddled or led astray. The Unwritten Wing is home to unrealised fragments of pure imagination, and AJ Hackwith cheerfully embraces the magical possibilities inherent in that. She doesn’t so much play with tropes as let them loose to express themselves. In the Unwritten Wing, an escaped hero must be returned to his (or her) pages; a damsel may be given the freedom of the damsel suite because honestly, they’ve been put through enough already.

But The Library of the Unwritten is also a portal fantasy romp of fallen angels and renegade demons in which the politics of Heaven and Hell are an excuse to visit Valhalla, an unnamed proto-Egyptian afterlife and Earth (charmingly, this last is the most exciting for our dead protagonists). Delightfully, it’s cogniscent that dealings with underworlds traditionally involve careful observation of arcane rules. A mortal soul cannot return to Earth without a ghost light (and woe betide the soul who remains amongst the living after their light flickers out); only a warrior is welcome in the halls of Valhalla (although the interpretation of this is delightfully broad).

And this isn’t just an exuberant fantasy of ideas and magical settings. The characters are just as much a part of the pleasure: Librarian Claire is stern and courageous, bolstered by the strength of her convictions and the guilt that haunts her. Brevity the former muse (and oh, how I loved that she was Brevity) is best when she can be brave on someone else’s behalf, full of compassion and determination. Leto is a cinnamon roll, a demon with an unexpected sense of right and wrong, uncomfortable with Claire calling Lucifer rude names and paying cabbies in stories instead of cash.

But it was the supporting cast that won me over. Walter the reluctant guardian of portals is delightfully reminiscent of Labyrinth‘s False Alarms; Arlid the Raven captain of Valhalla is staggeringly sure of herself. The damsels were my first inkling of what the climax might involve and the ones who truly stole my heart. I love that we never meet Lucifer, and it is – by the end – still impossible to judge if this version of him would be toe-tinglingly horrific or terrifyingly urbane.

Hackwith seeds her narrative with clues to historic secrets and future betrayals – those paying attention are unlikely to be surprised by the plot’s twists and turns – but it’s a pure joy to watch it unfold. There’s a deep satisfaction as a reader in seeing a story you want to see told told well, and The Library of the Unwritten is told exceptionally well, maximising the narrative pay-off in its final act.

Expect to finish it breathless, teary-eyed, laughing and more than ready to tackle the sequel (The Archive of the Forgotten) when it appears later this year. Because like any good story, The Library of the Unwritten sets up a world you can’t wait to get back to…

I received a free copy from the publisher in exchange for an honest review.