Janet Frame, alongside Katherine Mansfield, is New Zealand's most celebrated writer. As commentators have observed, both write with an unpretentious eccentricity, both have a flair for poetic metaphor, both convey utter emotional authenticity. And both were mentally fragile.

Frame, as Jane Campion's film An Angel at My Table harrowingly captures, spent years assigned to psychiatric hospitals where a misdiagnosis labelled her as schizophrenic and she narrowly escaped a lobotomy. Of this period she said, “I inhabited a territory of loneliness which resembles the place where the dying spend their time before death, and from where those who doreturn to the world bring a unique point of view that is a nightmare, a treasure, and a lifelong possession”.

Frame wrote Towards Another Summer in 1963, but the manuscript was set aside since she apparently felt that the novel was too revealingly autobiographical. This is the only aspect of this captivating book that confounded me. For if it is autobiography it is of the most innocuous kind. But writers are entitled to their public sensitivities and we must be grateful to the Janet Frame Trust for making the decision to publish it posthumously alongside a new selection of Frame's poems (Storms Will Tell by Bloodaxe Books).

The novel's protagonist, Grace Cleave, is herself a New Zealand novelist who has migrated to a shabby London flat where she is completing her second book. The theme of migration is central. Out of a strange, but instantly compelling conviction that she is “a migratory bird”, she accepts an invitation to spend a weekend up North with a couple with whom she is barely acquainted. (She arrives unaware even that they have children.)

The novel charts the two fraught days she spends in this alien household and it is crucial to the tone of the book that the couple esteem their guest's work and are nothing but welcoming. For a while, it seems possible that there is an undercurrent of erotic interest between Grace and her journalist host, Phillip, but it becomes clear that nothing so conventional is being attempted. His wife, Anne, is also from New Zealand, a good mother and a natural homemaker, and it is this that helps to prompt Grace's labile consciousness into the dizzying play between past and present which initiates a return to the bewildering relocations of her childhood.

“Home” is a complex and emotionally ambiguous concept for most of us and part of Frame's special gift is her visionary's refusal - or inabil-ity - to diminish the stark impact of early experience with the perspectives of adulthood. The horror and the glory remain intact. (Almost certainly it was this faculty that led to the misdiagnosis of schizophrenia.) Trapped in an unknown milieu, Grace's mind metamorphoses into the “migratory bird” that flies through time and space to revisit her own family: the exhausted mother, desperately failing to manage her brood of children, her faintly glamorous father, whose job on the railways was the cause of the family's constant and destabilising “shifts”, and the ever-expanding tribe of siblings for whom Grace cared with an anxious zeal, which, we guess, as with Frame, have vitiated her ability to enter into later relationships. One feature of the book is the disastrous mismatch between what Grace supposes is her hosts' conception of her as a vaunted novelist and her dismaying inability to communicate with them.

As her mind wheels, words stick fast and she balks like a nervy horse at the hurdles of even the simplest social interaction. For Grace, all thresholds provoke alarm because of “the human beings who might cross them”. In particular, she fears the children whose presence she hadn't bargained for. Here again, Frame demonstrates her fantastic acuteness, for the clear-sightedness of children is indeed scary: they see into us, and until the habit is socialised out of them will report what they see with alarming frankness. “Mummy, Grace-Cleave's crying, Grace-Cleave's crying,” Sarah, the daughter, exclaims when Grace is overcome on hearing Bach. And yet it is the children who understand Grace, recognising her for one of their own. When she finally plucks up courage to announce her early departure from this polite circle of hell, it is Sarah who conveys that she will miss her.

All of us will have known the agony of feeling out of place in another's domain. What is so remarkable about Frame is her ability to raise such quotidian crises to the level of comi-tragedy.

Towards Another Summer by Janet Frame
Virago £12.99, Buy the book here

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