In Border Crossing, Pat Barker’s last novel, a child called Danny Miller became a young man called Ian Wilkinson, the name change signalling his attempt to shed a previous identity, that of a 10-year-old boy who has brutally murdered an elderly woman. Both characters were reminiscent of Billy Prior, the ambiguous, menacing figure from Barker’s Regeneration trilogy, and now Danny/Ian surfaces again, this time as Peter Wingrave, an odd-jobbing gardener with aspirations to write, who provokes in all who meet him feelings of unease, mistrust and uncomfortable introspection.

From the vicar who both conceals Peter’s background and thrusts him into the wider community as part of a convict rehabilitation scheme, to Kate Frobisher, a widowed sculptor who reluctantly employs him as an assistant after a car accident leaves her incapacitated, Peter’s uncanny ability to insinuate himself into other people’s lives is a powerful metaphor for one of Barker’s central themes: that we might not always be able to recognise the evil in our midst, that it might present itself obliquely, and that, once arrived, it might corrupt our point of view entirely.

Or it might simply be that there are other, more readily identifiable evils already claiming our attention. Kate’s husband Ben, a photographer, has been killed in Afghanistan; his colleague, Stephen, a foreign correspondent who witnessed his death, now arrives in the countryside near Newcastle to write a book about the way that war is represented. He is especially besieged by flashbacks to the face of a dead, raped girl that he and Ben stumbled across in Sarajevo: “she was waiting for him,” he reflects, “that’s the way it felt. She had something to say to him, but he’d never managed to listen, or not in the right way”. Settling in a vacant cottage owned by his brother — the market for holiday lets having collapsed since the area was ravaged by foot and mouth — he is a stone’s throw from the studio in which Kate labours anxiously on her latest commission, a vast statue of Christ. Unwittingly, he has stumbled into another war zone.

Battles are being fought on all sorts of fronts, and with varying degrees of significance for the combatants. On the sidelines, Stephen’s brother and his wife are locked in a collapsing marriage that deflects their attention from their young son, recently diagnosed with Asberger’s syndrome, an echo of Danny Miller’s dissociations; Kate remembers the “flake of singed cowhide” that drifted onto her face from a burning cattle pyre, all the while knowing that “she would never, never, never be able to accept” Ben’s death; Stephen himself struggles with his conscience when he becomes deeply sexually involved with Justine, the vicar’s 19-year-old daughter.

But despite carefully constructing several layers of conflict — personal, psychological, social — Barker allows the main action to wind itself around the twin poles of Kate and Stephen. The novel’s title is deftly alluded to when Kate makes the chance discovery that Peter’s spectacles hold nothing but clear glass; she is unnerved precisely because his deception seems to have no point. Later, in one of the novel’s eeriest, most disturbing scenes, she watches him dressing up in her work clothes and standing over the half-formed sculpture, acting out her movements with hammer and chisel, a piece of mimicry that leaves her feeling both violated and complicit.

For Stephen, the problem of representation and imitation becomes more acute after he sees a photograph that Ben took of the raped girl in Sarajevo, and realises that, in one crucial respect, it fails to convey the truth. Can tweaking the material facts be regarded as falsifying them? Do Peter’s psychopathic short stories mean that he is a psychopath? Stephen’s concern, encapsulated by the novel’s epigraph, taken from Goya — “One cannot look at this. I saw it. This is the truth” — is also Barker’s, as she worries away at problems of perspective, involvement and detachment. Even the strength of that focus, though, can distort: as Justine warns Stephen, “people get into darkness, to the point where it’s the light that hurts”.

Double Vision is, in subject matter and theme, a bleak and overwhelmingly serious novel, although there are unexpected moments when it suddenly veers in tone towards something much lighter. There is also a sense in which Barker, by increasing the number of narrative threads, has also diluted them; Border Crossing was, in many ways, a stronger and more affecting book. Yet she still has a quite extraordinary ability to combine complexity and clarity, and to make both seem parts of the same whole.

DOUBLE VISION by Pat Barker

H Hamilton, £16.99, pp307

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