Not surprisingly, female novelists (Virginia Woolf, Angela Carter, Jeanette Winterson) are fascinated by the pressure on women to fit into the narrow mould of others' expectations. Impossible Saints, though it appears to explore many worlds, always keeps to this theme.
Michele Roberts's central story, of a nun who may or may not be a saint, is interleaved with the lives of "impossible" saints - women, ancient and modern, often drawn from the legends of real saints, who come to grief when they hit the barriers.
We begin in a chapel full of relics of holy women. The holiest have been given special reliquaries, but there is a surplus of bones which have been used to decorate the chapel walls in an elaborate, bony mosaic. And this perfectly expresses Roberts's book - countless lives, woven into one seamless whole.
The principal heroine is Josephine, growing up at the time of the Inquisition. Josephine is the darling of her rich father, until he catches her reading her dead mother's "forbidden" books. Here are two major motifs: the first, the hidden book or manuscript, a retreat of sensual delights which will get the writer or reader into serious trouble if discovered; the second, the problematical relationship between father and daughter. In this world, virgin daughters are precious jewels, and used daughters are rubbish.
Josephine, horrified by her father's rage, retreats into a convent. There she stays for the next 20 years, hoping to save her soul from the flames. Then, like St Teresa of Avila (by whose writings Roberts says she was "partly inspired"), Josephine is granted an ecstatic vision of Jesus Christ. "He took her in his arms, and laid her close to his heart, so that she thought she would faint with joy."
But the vision nearly gets Josephine burned at the stake for heresy. To save herself, the authorities make her write a book of her life. Using all her arts of deception, she produces a document of feminine goody-goodiness. "The priests were used to woman bowing and genuflecting in front of them ... uttering formulae of limitedness and humility. Josephine's self-abasement could have been read as boasts and irony and mockery but was not."
Far from it. The hated book is declared suitable reading for young Catholic girls. Josephine will not be burned, but she pays for her life by losing her visions and her faith. In secret, she begins to write another book which we never see, but guess to be a rich, subversive feast.
She leaves the convent for the house of her cousin, Magdalena: a sort of anti-convent, set in a garden and dedicated to pleasure. Here, she consummates her love for her favourite priest, Father Lucian, and plans a new order of nuns which will cater to the real needs of women.
Roberts plaits her stories together superbly, laying out words for their sheer deliciousness. It is easy to sink voluptuously into imagery so beautiful, but Michele Roberts is too skilled a storyteller to let her prose distract from her tightly-controlled theme. Impossible Saints, like the life of a real saint, is dangerously close to perfection.