In Margaret Atwood’s brilliant new novel of nineteenth-century Canada there is a character called Jeremiah, a pedlar, whose diverse and enticing wares are welcomed in almost any house. Some of his linens and ribbons are new, and some are what is now known as  ‘previously owned’, but all are crisp, fresh and desirable. The pedlar can also eat fire, tell fortunes and talk with the dead. Jeremiah is the one with whom Atwood identifies. Her variety is dazzling; she meanders, yet travels with a purpose; she can also put on magic shows.

Her main character is Grace Marks, a murderess. Grace thinks: ‘It has a smell to it, that word – musky and oppressive, like dead flowers in a vase. Sometimes I whisper it over to myself: Murderess, Murderess.’ It rustles, like a taffeta skirt along the floor.’

Grace was a little girl, just fifteen, when she was tried and sentenced to hang. She was poor, Irish, and an emigrant whose mother died on the ship; she escaped her violent father and clinging brothers and sisters only by selling herself into virtual slavery as a domestic servant. Atwood treats her without sentimentality. These are the facts of her life, replicated again and again in other women’s stories.

Grace’s situation eased. She found a job in the country outside Toronto. Her employer was Mr Kinnear, a well-meaning gentleman. His private life was improper; his housekeeper, bounding Nancy, shared his bed. McDermott, the outdoor man, grew grievances in his spare time; sulked and fumed, desired Nancy, and desired Grace. For sulking, he was dismissed; took an axe to Nancy, shot Mr Kinnear. Ran away with Grace Marks, was caught very soon, just over the US border, in possession of the dead man’s horse and wagon, with Grace who was wearing Nancy’s frock. The year was 1843.

This is a true story; as true as Atwood can make it. and she feels a responsibility in that line. The acknowledgements at the end of the book reveal that in 1974 she wrote a television play based on the case. Now she sees that the evidence on which she relied cannot be taken as definitive. She doubts almost everything, questions everything. ‘I have of course,’ she says ‘fictionalised historical events, although not more so than many commentators on this case who claim to be writing history.’

Grace did not hang, though the manservant did. She was so young, her lawyer said, so mad, and if not mad, then half-witted. For some twenty-five years, she was shunted between prison and asylum. Atwood sends a young doctor to see her, a would be ‘alienist’ who hopes to establish his own model establishment for the treatment of the aberrant. Is Grace mad, or bad? The doctor cannot know. Nor can we. But Atwood tells us her story in her singular voice – ingenuous yet knowing, always surprised and always surprising.

Atwood has moved into teasing intellectual territory, where few have ventured: the dense undergrowth of Western thought where the nascent semi-science of psychiatry and the nascent semi-art of spiritualism met each other and mated, and gave birth to some sharp-toothed offspring. Thematically, and in its brilliant lyrical intensity, the book has something in common with Susan Fromberg Shaeffer’s novel The Madness of a Seduced Woman. The prison and shipboard scenes recall Lesley Glaister’s Partial Eclipse. Like Glaister’s prose, Atwood’s is searching, so intimate that it seems to be written on the skin. In the centre of her novel, Atwood’s writing is simply visceral – impressive at a horribly deep level. She digs her images into her story, so that they blow up like psychic land mines when the reader’s perception brushes against them.

The book brims with ideas, expressed through the narrative with subtlety but no obscurity. Atwood has no need to be obscure. She is formidably intelligent, and a formidably accomplished novelist. She is so exact and faithful in detail that she carries utter conviction, but she is a realist with wings: with the firefly’s wings, or the angel’s wings that haunt, when she is in her narrow cell, the child-woman with the ‘plain name of Grace.’