Muriel Spark, that novelist of genius, does not often write about food. But in A Far Cry From Kensington, in which she returns to the London of the 1950s, food plays a satisfying role in the characteristic Sparkian moral universe, where cruelty is explored, and good skirmishes with evil.

The book's narrator, Mrs Hawkins, is a young war widow who works in publishing. She deals with authors: "There was something about me, Mrs Hawkins, that invited confidences. I was abundantly aware of it, and indeed abundance was the impression I gave. I was massive in size, strong-muscled, huge-bosomed, with wide hips, hefty long legs, a bulging belly and fat backside." She is comfortable in her fatness, admired for her largeness and motherly look, used to being offered seats on the Tube by other young women who assume she is pregnant, graciously accepting of older men's invitations to dinner at the Savoy. There she eats salmon mousse, the speciality, followed by "something exotic. This was in the last few weeks of all food rationing and the Savoy was making an anticipatory splash."

Trouble begins when Mrs Hawkins tells Hector Bartlett, hack and hanger-on to the famous novelist Emma Loy, that he is a "pisseur de copie". Emma gets Mrs Hawkins the sack. For her next job, she is taken on by a publishing firm whose directors like employing freaks: authors and printers can't possibly be nasty to them. Mrs Hawkins, realising she is valued for her fatness, decides to lose weight: "I can tell you that if there's nothing wrong with you except fat it is easy to get thin. You eat and drink the same as always, only half. If you are handed a plate of food, leave half; if you have to help yourself, take half." None of our modern fuss and introspection about diets; our neuroses and excuses.

The splendid Mrs Hawkins adds a tip about the necessary will-power: "You should think of will-power as something that never exists in the present tense, only in the future and the past.

At one moment you have decided to do or refrain from an action

and the next moment you have already done or refrained . . . I

offer this advice without fee; it is included in the price of this book."

The novel rushes on its course: the characters dabble in forgery, slander, blackmail and attempted murder. One is driven to suicide. Hector Bartlett is revealed as the chief perpetrator of evil when Mrs Hawkins, placidly consuming her pub lunch of half a ham sandwich and half a glass of port, watches him feed a dog a sausage roll dipped in hot mustard. Mrs Hawkins speaks feelingly of the edginess that goes with eating less than you are used to. But, on the other hand, she acquires a normal shape, cheekbones, sexual hunger, a lover.