In 1963, the New Zealand writer Janet Frame (perhaps best known for her autobiography, An Angel at My Table) hit writer's block. As a diversion, she wrote a short autobiographical novel that she then put aside, saying it was too personal for publication during her lifetime. The appearance, four years after Frame's death, of Towards Another Summer is a literary treat that has generated much excitement.

It is the story of a weekend in the life of Grace Cleave, like Frame herself a New Zealander in her thirties living in London and writing novels. Grace seems pretty unhinged. There are references to psychiatrists and hospital stays. She also believes she has turned into a “migratory bird”. Invited to stay with a journalist, Philip, and his family in the north of England, Grace braces herself for “a promise of nightmare”. Terrified of social interaction, almost mute in company and feeling herself transmogrified, she somehow manages to get there. The weekend is agonising - for everybody.

Grace barely speaks. Instead, her thoughts soar and circle and throb in hallucinatory patterns. She explores the meaning of “home” through memories, poetry, snatches of song. There are glimpses of her childhood - a father who worked on the railways, a frazzled mother covered head to toe in weeping sores, trying to cope with too many children and constant relocations. “The Southern Cross cuts through my heart instead of through the sky,” she says. But since Grace also has a fear of “thresholds, and the human beings who might cross them”, it is clear that home (whichever hemisphere that may be) is never going to be a place of safety. And in Philip's house, her status as a guest on foreign territory becomes almost unbearable. She is tormented throughout the weekend by her neuroses; unable to break out and communicate her feelings even when social niceties require it. Interaction is panic management: when visited, early in the book, by a young couple, she closes the door with relief. “Another encounter with people successfully concluded without screams, or tears or too much confusion.”

In this frighteningly fluid world, where thoughts migrate from present to distant past and back again, words become more concrete than buildings or bodies or even historical events. The war, for Grace, is “epitomised” by “the paper on which books of those years were printed”. Picking up a collection of New Zealand verse, she clings to the architecture of the print, “the beautiful Ms and Ns like archways, the lintel Ts, the delicately throated Rs”.

All this makes for fraught reading, and one would expect little else from a book that Frame - hardly shy of raw autobiography - considered too close to the bone. Much of the power of this novel, however, lies simply in the breathtaking economy of the prose. Grace fears children. She believes they will see through her and in doing so somehow make her disintegrate. When she first encounters Philip's small offspring, in long white nightgowns, they seem fairy-like, loaded with myth and malevolence. One curt sentence conveys this perfectly: “Staring solemnly the two children flickered around Grace.”

This is not exactly a fun read. It generates a sense of claustrophobia and exhaustion, and sometimes impatience. It really is agony to be Grace Cleave. Whether this posthumous book can offer new insight into Frame's life or psyche is also surely debatable. After all, a migratory bird is surely not the most reliable witness.

Towards Another Summer by Janet Frame
Virago £12.99 pp215. Buy the book from Books First £11.69 including free delivery

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