Louise Doughty has done it again. A Bird in Winter is her 10th novel and it follows a string of addictive thrillers (including the bestsellers Platform Seven, Apple Tree Yard and Whatever You Love) in which she writes about a modern woman on the edge. Here, an office worker walks out on her life, abandoning her job and family. But is this a fanciful midlife adventure, or is she fleeing something?

For the protagonist, Bird, flight comes first with desperate urgency, then with paranoia and hypervigilance: “I want to be right by the doors and windows on the ground floor so I will wake up if someone tries to break in… Sometimes I get out from under the duvet and go to the small window that looks out over the road, peering through the narrow gap between the window frame and the curtain.” It turns out that Bird’s paranoia is justified: she is indeed being hunted. We discover her professional history in the army and the secret service and deduce that she is not a disgruntled everywoman who’s had it with corporate life, but a government spy with substance, secrets and real enemies who pursue her northwards, as far as Iceland.

There’s a touch of reality TV about it all – a combination of Hunted and Alone, perhaps, in which people have to survive in terrifying places such as “the north” and “the countryside”. A Bird in Winter explores the horror of being followed, but it also taps into universal fantasies of what it would be like to drop everything and go on the run, taking on different personae and relying on survival skills gleaned from scouts’ manuals and spymasters’ training. While Bird’s primary sensation might be dread, for the reader the story is great fun.

It’s simply pleasurable to read a writer who has found her groove and produces smart, riveting and (seemingly) effortless entertainment. Apple Tree Yard was adapted by the BBC, which also made Crossfire, the series she created and wrote. Inevitably, I found myself playing fantasy casting and considering various grimly telegenic crime locations while reading A Bird in Winter. Yet another Doughty adaptation, Platform Seven, will be a headline release for ITV this autumn. Until then, this page-turner will leave you fully satisfied.

• A Bird in Winter by Louise Doughty is published by Faber (£16.99). To support the Guardian and Observer order your copy at guardianbookshop.com. Delivery charges may apply