The Dream Archipelago is a vast string of thousands of islands, wrapping themselves around the world between two great continents. Some of them are deserts, some are home to great cities and others have been riddled with tunnels and turned into gigantic musical instruments. The Islanders is a gazetteer to the islands...and a murder story. It's also a musing on the nature of art and the artists who make it.

The Islanders is Christopher Priest's first novel in almost a decade, a fact which itself makes it one of the most interesting books to be released this year. His previous novel, The Separation, a stimulating and layered book about alternate versions of WWII, was one of the very finest novels of the 2000s. True to expectations, Priest has returned with a fiercely intelligent book that works on multiple different levels and which rewards close, thoughtful reading.

The Islanders initially appears to be a travel gazetteer, a Lonely Planet guide to a place that doesn't exist. Several islands are presented with geographic information, notes on places of interest and thoughts on locations to visit. Then we get entries which are short stories (sometimes only tangentially involving the island the entry is named after), or exchanges of correspondence between people on different islands. One entry is a succession of court and police documents revolving around a murder, followed by an extract from a much-later-published book that exonerates the murderer. Later entries in the book seem to clarify what really happened in this case, but in the process open up more questions than are answered. Oh, a key figure the gazetteer references frequently is revealed to be dead, despite him having produced an introduction to the book (apparently after reading it). Maybe he faked his death. Or this is a newer edition with the old introduction left intact. Or something else has happened.

The Islanders defies easy categorisation. It's not a novel in the traditional sense but it has an over-arcing storyline. It isn't a collection of short stories either, though it does contain several distinct and self-contained narratives. It isn't a companion or guidebook, though readers of Priest's earlier novel The Affirmation or short story collection The Dream Archipelago will find rewards in using it as such. It is hugely metafictional in that themes, tropes and ideas that Priest has been working on for years recur and are explored: doppelgangers, twins, conflicted memories, magicians, performance art and shifting realities feature and are referenced. At several points Priest seems to be commenting about his own works rather than the imaginary ones written by a protagonist...until one of those books turns out to be called The Affirmation, the same title as one of Priest's earlier, best novels. A character's suggestion that a work be split into four sections and then experienced in reverse order may be a clue as to how the novel should be read...but may be a red herring. Several key moments of wry humour (The Islanders is probably Priest's funniest book) suggest that we shouldn't be taking the endeavour seriously. Moments of dark, psychological horror suggest we should.

The novel embraces its gazetteer format. References to another island in an entry may be a clue that a vital piece of information can be found in the corresponding chapter about the other island. Sometimes this is the case, sometimes it isn't. Recurring names (some of them possibly aliases) and references to tunnels and havens provide links that bind the book together. The strangest chapter appears to be divorced from the rest of the book altogether, but subtle clues suggest curious relationships with the rest of the book and indeed with other of Priest's works (though foreknowledge of these is not required). The interlinking tapestry of references, names and events forms a puzzle that the reader is invited to try to piece together, except that the pieces don't always fit together and indeed, some appear to be missing altogether.

The Islanders ( ***** ) is a weird book. It's also funny, warm and smart. It's also cold, alienating and dark. It's certainly self-contradictory. The only thing I can say with certainty about it is that it is about islands and the people who live on them, and if there is a better, more thought-provoking and rewarding novel published this year I will be surprised. The book is available now in the UK and on import in the USA.