Rajaniemi’s pacy debut novel is set in a far future where both Jupiter and Phobos have been turned into suns in the aftermath of a war between the godlike Sobornost, who control most of the inner solar system, and the Zoku, now exiled to Mars from their Saturnian home.

On Mars all off-world tech is proscribed. The city called the Oubliette is constantly on the move, built on platforms which change their relative position as it is carried across Hellas Basin on vast articulated legs. Rajaniemi does not fetishise this creation as many another author would. Far from being almost a character in its own right the city is merely an exotic backdrop for his story, not its focus.

In the Oubliette, interactions between people (and buildings) are mediated by technology known as exomemory which captures every thought, dream and action. A filtering system known as gevulot acts as a privacy screen but is opened for speech and donation of information packets called co-memories.

The city’s inhabitants all carry Watches which store the Time they use as money. When your Time runs out, death follows. Resurrection Men decant memories and implant them in a new body in which to serve the city as one of the Quiet till enough credit has been accrued to live normally again. On occasion criminals dubbed gogol pirates deliberately kill in order to steal the deceased’s memories and enslave the minds. This is anathema to anyone from the Oubliette (but philosophically it surely differs from being Quiet only in degree.) Tzadikkim, a vigilante-type group with enhanced powers, act as an informal police.

The narrative is shared between the first person account of Jean le Flambeur, the quantum thief of the title, and the third person viewpoints of an Oortian, Mieli, who kicks the novel off by springing Jean from an unusual prison round Saturn, and the somewhat too intuitive detective Isodore Beautrelet. Both Jean and Mieli have (rarely used) Sobornost enhancements. In addition, several Interludes fill in backstory and -ground.

The text can be dense at times. Rajaniemi deploys technological terminology with a flourish; qdots, ghostguns, qupting, Bose-Einstein Condensate ammunition, quantum entanglement rings, qubits, but these can be allowed to wash over any technophobic reader prepared to follow the flow.

By implication Rajaniemi emphasises the importance of memory, not only in the idea of exomemory or the uploading/decanting of personality but also as a component of individual identity. Jean le Flambeur has hidden his past from himself and has no recall of it until others restore it bit by bit via gevulot exchanges.

Rajaniemi’s Finnish origins are most revealed by some of the names he uses. Mieli’s spidership is called Perhonen - butterfly - and he slips in a Finnish expletive in the guise of an Oortian god. There are also borrowings from Japanese, Hebrew and Russian and a subtle Sherlock Holmes reference.

“The Quantum Thief” is bursting with ideas and there are sufficient action/battle scenes to slake any thirst for vicarious violence but sometimes it seems as if incidents are present in order to fill in background rather than being necessary to the plot. The motivations of some of the characters are obscure and despite the prominence of gevulot in the Oubliette, conversations and interactions seem to be more or less unaltered in comparison to our familiar world, though had Rajaniemi presented them otherwise they may have been unintelligible.

The denouement brings all the threads together satisfyingly while the final Interlude sheds additional light on the proceedings and sets up possible scenarios for sequels - for which there will likely be an avid audience.