When Tony Blair paid tribute to the victims of 9/11, he chose to end his speech with a quote from one of his favourite novels, The Bridge of San Luis Rey by Thornton Wilder. Wilder’s 1927 masterpiece traces the (imagined) journeys of five people as they converge on a rickety Peruvian bridge that collapses under their weight, killing them all. It is a meditation on chance and fate, on the fragility of life.

Now Francis Spufford has followed up his dazzling debut novel, Golden Hill, with a book that seeks to step into the reflection of The Bridge of San Luis Rey, asking not what brought a group of people to their untimely death, but what would have happened had they been spared.

In his acknowledgments, Spufford writes of the inspiration for the book — a memorial to those killed by the V2 that fell on the Woolworths shop on New Cross Road in 1944. “Of the 168 people who died,” he tells us, “fifteen were aged eleven or under”. Light Perpetual opens with a reimagining of that attack, the Woolworth’s transported to the fictional South London suburb of Bexford. Time is slowed almost to a stop as, through “a hairline crack in a Saturday lunchtime in November 1944”, a bomb drops.

We zero in on five children, the unlikely heroes of the novel. “Jo and Valerie with their mum, wearing tam-o’-shanters knitted from wool scraps; Alec with his, spindly knees showing beneath his shorts; Ben gripped firmly by his, and looking slightly mazed, as usual; chunky Vernon with his grandma, product of a household where they never seem to run quite as short of the basics as other people do.” All are killed.

What is lost, Spufford writes, in his sure-footed, avuncular authorial voice, “is not just the children’s present existence”; rather “it’s all the futures they won’t get, too. All the would-be’s, might-be’s, could-be’s of the decades to come.” And then he expresses the impulse that drives the whole book, the engine of its narrative: “How can that loss be measured, how can that loss be known, except by laying this absence, now and onwards, against some other version of the reel of time, where might-be and could-be and would-be still may be?”

Spufford maps out the lives of the five children, spared by an act of writerly benevolence, as they make their way through the second half of the 20th century and into the 21st. I was reminded of the death-defying bent of two other recent novels — Kate Atkinson’s Life After Life and Paul Auster’s 4 3 2 1 — both of which share with Light Perpetual a kind of radiant goodness, a sense that the world is a better place for having such books within them.

We drop into the lives of Jo, Val, Vern, Alec and Ben at five different points in time: 1949, 1964, 1979, 1994 and 2009. We see their triumphs and their failures, the way their lives overlap and intersect subtly, obscurely, in the way that such lives would. We’ve seen the power of this episodic approach to storytelling in David Nicholls’s One Day, where much of the filling-in is left to the imagination. It makes for a pleasingly collaborative reading experience.

Jo is a singer in a band, The Tearaways, who have an “Honor-Blackman-in-The-Avengers thing going” and then becomes a music teacher. Val, her sister, marries a mod who becomes a skinhead, following him down into the gutter politics of the National Front before emerging, transformed. Vern is a boy on the make with dreams of skyscrapers and shopping malls on Bexford High Street. Alec is clever, a typesetter at The Times; he marries and is divorced, finds love late in life.

Ben’s story is perhaps the most moving of all. We first meet him as he is hoisted on to his father’s shoulders at a Millwall game. When we next encounter him, he’s in a psychiatric hospital, dosed up on Largactil, stuttering and wooly headed. His recovery is slow and tentative, but with each new iteration of his life he is a little better, and the reader cheers him all the way.

Themes emerge as we move through time, one of which is the nature of time itself. Ben’s recovery is only one of a number of ways in which Spufford seeks to show the strength of the human spirit, the way that time, eventually, heals. All of the characters, even wide boy Vern, gain wisdom and the consolation of perspective as the years pass. It’s a book that is also a social history of South London, showing the frictions and fissures, the ugly insularity as well as the generosity and decency.

Towards the end of the novel, Alec speaks admiringly of Robert Tressell’s The Ragged Trousered Philanthropists: “The only novel in the English language where the author thought plastering was interesting enough to put in.” Like Tressell’s book, Light Perpetual’s brilliance lies in the emotion and drama it wrings from the ordinary — but profoundly meaningful — experiences of its protagonists. Spufford’s prose, which is never showy, but always beautifully accurate, confers an extraordinary dignity on the lives of these imagined children, recovered from the rubble of a fictional bomb site.

Light Perpetual, by Francis Spufford, Faber & Faber, RRP£16.99, 336 pages

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