“It sometimes seemed to Keith that the English novel … asked only one question. Will she fall? Will she fall, this woman?” But in Martin Amis’ new novel, The Pregnant Widow, it is the man, Keith, who falls, time and again – who stumbles, trips, fails and falls in love. It is the summer of 1970. The Sexual Revolution is in its infancy, The Female Eunuch is in utero and Keith, his girlfriend Lily and a group of friends are 20. They arrive at a castle in Italy for a summer idyll. The sexual and romantic turbulence of the summer will influence the rest of Keith’s life; nearly 40 years and three wives later, the delayed shock of it knocks him flat.

A big book with big themes, at the same time witty, intimate and gripping, The Pregnant Widow takes its title from Alexander Herzen’s observation that revolution creates “not an heir but a pregnant widow”. Positing the separation of sex and love as both possibility and Grail, the Sexual Revolution didn’t so much create a new world as an anxious pause between eras. Within Keith, romanticism grapples with opportunism, poetry with ‘kitchen sink’ realism, and conscience with the “instrument of yearning” that is the body.

The female characters in whose orbit Keith spins are simultaneously archetypal and complex. Among them are his sororal lover Lily, with her intelligent instinct for self-preservation; his beloved sister Violet, bent on self-destruction; the absurdly desirable Scheherazade; and the enigmatic Gloria Beautyman, whose grand entrance to the story, in a riveting spectacle of shame, is one of the book’s most enduring images.

The Pregnant Widow is gravid with literary references: Blake, Rilke, Larkin, Wordsworth and many others weave through the novel’s dense texture, and the legend of Narcissus (from Ovid via Ted Hughes) shimmers up through the mirrors and pools, fountains and baths that trick moisture into nearly every part of the story. Austen and Shakespeare lay the tallest shadows over this hot, sunny landscape with its comedy of manners, its star-crossed lovers, sexual cross-dressing, sense and sensibility, pride and prejudice all jumbled up in a youthful midsummer night’s dream in Italy.

Amis intended this long-delayed book to be more autobiographical than it turned out; the lovely, heart-rending Violet was based closely on his own (deceased) sister Sally. The author’s obsession with the position of Muslims in Western societies also manifests in a sub-theme that feels less organic than purposeful – to my mind, the novel’s only major misstep. More often in The Pregnant Widow, Amis – a writer’s writer – takes my breath away: “The day was coming in like a current.” “Scheherazade was decanting herself downward through the three tiers of the terraced gradient …” I am haunted still by the terrible, comic image of the tiny Italian aristocrat Adriano, a perfect miniature of manhood, all muscle and bluff and crazy bravery, pinwheeling around the exercise bar at the castle pool in his campaign to win the attention of his beloved. In this English novel, everyone falls.