Cambridge is sweltering, during an unusually hot summer. To Jackson Brodie, former police inspector turned private investigator, the world consists of one accounting sheet – Lost on the left, Found on the right – and the two never seem to balance. Jackson has never felt at home in Cambridge, and has a failed marriage to prove it.

It's a day like any other for security chief Tracy Waterhouse, until she makes a purchase she hadn't bargained for. One moment of madness is all it takes for Tracy's humdrum world to be turned upside down, the tedium of everyday life replaced by fear and danger at every turn.

In 1940, 18-year old Juliet Armstrong is reluctantly recruited into the world of espionage. Sent to an obscure department of MI5 tasked with monitoring the comings and goings of British Fascist sympathisers, she discovers the work to be by turns both tedious and terrifying. But after the war has ended, she presumes the events of those years have been relegated to the past for ever. Ten years later, now a producer at the BBC, Juliet is unexpectedly confronted by figures from her past. A different war is being fought now, on a different battleground, but Juliet finds herself once more under threat.

Kate Atkinson’s dazzling Life After Life, one of the top-selling adult books of 2014, explored the possibility of infinite chances, as Ursula Todd lived through the turbulent events of the last century again and again. In A God in Ruins, Atkinson turns her focus on Ursula’s beloved younger brother, Teddy – would-be poet, RAF bomber pilot, husband, and father – as he navigates the perils and progress of the 20th century. For all Teddy endures in battle, his greatest challenge will be to face living in a future he never expected to have.

Jackson Brodie has relocated to a quiet seaside village in North Yorkshire, in the occasional company of his recalcitrant teenage son Nathan and ageing Labrador Dido, both at the discretion of his former partner Julia. It’s a picturesque setting, but there’s something darker lurking behind the scenes. Jackson’s current job, gathering proof of an unfaithful husband for his suspicious wife, seems straightforward, but a chance encounter with a desperate man on a crumbling cliff leads him into a sinister network - and back into the path of someone from his past.