These novels both explore, in very different ways, what Aldous Huxley called the “appalling dangers of family life”. In The Steep Approach to Garbadale, Iain Banks introduces us to the sprawling, scattered and extremely rich Wopuld clan, owners and controllers of a family business in board and computer games that has made most of them wealthy, with the prospect of a huge windfall if the company’s sale to an American corporation goes through. In Blenheim Orchard, the family is more nuclear in every sense, including its potential to detonate: a middle-class Oxford couple (he a failed academic, she a fearsomely capable small businesswoman and local campaigner) and their children.

Tim Pears has always been drawn to examining the passing of time, from his first novel, In the Place of Fallen Leaves, where the rural setting seemed to link the 1980s to a more distant past, to A Revolution of the Sun, in which a single year encompassed a world of changes. In Blenheim Orchard, the action takes place between June and September 2003, the first to last days of a hot summer, with each chapter dated like a diary. The setting is equally specific, grounded in and around Oxford; with a map of the city you could plot each journey, meeting or illicit liaison.

All this reality narrows the space for fiction to work, but Pears is a master at drawing significance out of the everyday. We witness the Pepins’ daughter making fudge, the youngest son’s method of helping his mother Sheena with the shopping, or Sheena’s approach to her regular swim. There is a deliberate teasing of our prejudices against all this middle-class self-satisfaction, a sense that any minute, between the earnest discussions of the war in Iraq, thedinner parties and picnics, and the endless bicycling, there will be a price to pay.

Ezra’s long-forgotten academic career is in anthropology, and although the tales of the Paraguayan Achia tribe’s lifestyle juxtaposed with that of the Pepins hardly feels like a new device, Pears uses it to good effect to reveal gradually how Ezra, despite his wife’s hopeful delusions on the subject, can never return to his fieldwork. His happiness lies far away from what she can imagine. Blenheim Orchard is not a dazzling novel, but its effects are built up cumulatively to paint a lasting portrait of a family breaking apart at almost glacial pace.

Banks still has a reputation, partly maintained by his alter ego as a science-fiction writer, for an imagination that acknowledges no boundaries. But his “straight” fiction has been increasingly rooted in real life. In The Steep Approach to Garbadale, the flights of fancy take place around the edges of the seemingly straightforward story of Alban Wopuld and his quest for fulfilment when his life is knocked off course by bereavement and the consequences of a disapproved-of adolescent affair with his cousin Sophie. Banks throws in disquisitions on the semiotics of games, global capitalism, global warming and the cruelties of rich families. If occasionally he gives the impression of allowing his verbal facility to get the better of him (two dotty aged aunts and their mishearings wear pretty thin, and inappropriately placed puns sprout like weeds), there is never any doubting his talent for telling a story. This novel has the reliable and satisfying completeness of a well-conceived game, with just the right degree of surprise and unpredictability.

David Horspool is an editor at the TLS. Both novels are available at Sunday Times Books First prices, £13.49 (Pears) and £15.99 (inc p&p), on 0870 165 8585

BLENHEIM ORCHARD by Tim Pears, Bloomsbury £14.99 pp403

THE STEEP APPROACH TO GARBADALE by Iain Banks, Little, Brown £17.99 pp390

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