Saturday by Ian McEwan

The brain inside the skull beneath the skin

Losing your five-year-old in a supermarket, or watching a man fall 300ft to his death from a balloon that you and he and others had collectively failed to anchor: some of Ian McEwan's finest novels open with emotionally arresting set pieces that hold and define the ensuing narrative. The Child in Time, which pursued themes of innocence and loss, and Enduring Love, which prolonged the trauma of that ballooning accident with nagging guilt and a deranged obsession, both flowed from appallingly visceral calamities that embroiled and bowled over their innocent protagonists. McEwan's characters swiftly learn that "innocence" is a mutable, morally complex state, never free from its annoying siblings, responsibility and guilt.

Losing your five-year-old in a supermarket, or watching a man fall 300ft to his death from a balloon that you and he and others had collectively failed to anchor: some of Ian McEwan's finest novels open with emotionally arresting set pieces that hold and define the ensuing narrative. The Child in Time, which pursued themes of innocence and loss, and Enduring Love, which prolonged the trauma of that ballooning accident with nagging guilt and a deranged obsession, both flowed from appallingly visceral calamities that embroiled and bowled over their innocent protagonists. McEwan's characters swiftly learn that "innocence" is a mutable, morally complex state, never free from its annoying siblings, responsibility and guilt.

This is what eminent neurosurgeon Henry Perowne discovers, as he works his way through what turns out to be a pretty hairy Saturday. The 50-page opening set piece of Saturday, though less cinematic than a ballooning accident, is magnificently meditative, and expansive without being flabby. From his bedroom window, Perowne witnesses the apocalyptic image of a comet in the night sky, which turns out to be a burning plane struggling over central London towards Heathrow. Or is it a terrorist attack? Instead of raising the alarm he makes love to his waking, beloved wife, Rosalind.

Seen from the small hours both outcomes, deliberate terror or terrible accident, are equally possible truths. Perowne muses on the famous conundrum of Schrödinger's Cat (whose death/life for the external observer is equally true until the box is opened for confirmation). This motif hangs over Perowne's day, framing a powerfully evolving theme of public and private responsibility for the consequences of action or inaction.

This particular Saturday is 15 February, 2003, the day on which millions converged on London to march against the imminent, though not yet certain, invasion of Iraq. Perowne gets up, buys some fish, visits his memory-less mother in a nursing home, calls in on his son Theo's band rehearsal and returns home to cook supper for a delicate family reunion. They are expecting Rosalind's cranky father, the poet John Grammaticus, who insulted the first literary success of their daughter Daisy, coming by train from her new lover in Paris.

Perowne's dreamy domestic warmth, vividly conveyed by McEwan's free-ranging, empathetic imagination, is sapped by the sense of unease flaring out behind his trajectory ever since witnessing the ominous non-comet. This unease materialises in the form of Baxter, the edgy BMW driver he collides with on his way to a squash game with a colleague. Perowne narrowly evades a beating by swiftly diagnosing the degenerative disease fuelling Baxter's hostility; but the undesirable side-effect of this is that he accidentally humiliates Baxter in front of his sidekicks.

McEwan seamlessly combines Perowne's anxiety over the state of the world with a richly detailed, ruminative celebration of his clinical work, his family and the exuberant, physical pleasures of life: wine, food, music. In stark contrast, Baxter is denied all Perowne's pleasures; but if his condition (trapped by a tiny genetic defect into an early, slavering demise) can be sympathised with on social or medical levels, his aggression cannot be condoned. How to balance succour with intervention?

In Baxter's bullying violence, McEwan crafts a very personal, in-your-face foil to the intractable arguments pro and con invasion, which Perowne is forced to articulate when Daisy arrives fresh from the massive Hyde Park anti-war rally to excoriate her father's balanced opinions. Their shockingly sudden, hot, sour row, within minutes of greeting each other after six months' absence, only underlines the moral complexity of the humanitarian dilemma. Perowne's reduced defence feels very much the nub of Saturday: no single course of action, including taking no action, is without ramifying consequence, potential casualty or guilt.

Refreshing and engrossing, Saturday has a pleasing intimacy, dense with revelation, and is not at all encumbered by dogmatic argument. Perowne is an admirable man grappling as best he can with an idea of the world and his responsible place in it. He rarely reads the fiction that his daughter prescribes for him because, as an atheist clinician, he wants the world explained factually, not reinvented as stories. McEwan's superb novel amply demonstrates how good fiction, by dramatising unwieldy and fraught ideas in a deeply personal narrative, can fashion the world into gobbets sometimes more digestible than factual reportage.

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