Bloomsbury £16.99 pp432

T C Boyle’s 2003 novel, Drop City, cast a coldly cynical eye on the sexual liberation movement of the 1960s, suggesting that the era’s free-love ethos was not quite as emancipating as the flower children might have wished. With The Inner Circle, he steps back several decades to depict one of the gurus of that revolution, the zoologist Alfred Kinsey, whose pioneering research forever changed the way Americans think about sex. But where Boyle’s previous novel was a bit too hard on his long-haired targets, this time out his satire is spot-on.

Boyle’s narrator is the evocatively named John Milk, a naive small-town boy who arrives at Kinsey’s Indiana University just before the second world war. He attends the professor’s infamous course on “the physiology of intramarital relations” to get close to the luscious Laura Feeney, and soon finds himself employed by the charismatic Kinsey at his Institute for Sex Research. Milk’s job is to help conduct the no-holds-barred interviews that were to provide the foundation for Kinsey’s ground-breaking 1948 study, Sexual Behavior in the Human Male. Employing some of the same zoological methods he used to study wasps, Kinsey set out to demystify sex, to tear away the veils of myth and romance from the carnal act. “They’ve had 3,000 years to go on about love,” he tells his critics.“Now give science a chance.”

Working at a time when undergraduate couples were forced by chaperones to keep one foot on the floor while seated together on the sofa, when “coitus out of wedlock was universally banned, masturbation illegal and sodomy a felony in most states”, Milk’s young eyes are jerked wide open. He learns that behind the veneer of hale American rectitude is a brave new world of adultery, homosexuality and practices such as “urethral insertion”. This sense of discovery extends to his own psyche when he becomes involved in affairs with Kinsey and Kinsey’s wife, both adherents to the professor’s belief that “there is no sexual act between consenting parties that is in any way qualitatively different from any other, no matter what the prevailing ethos of a society may be”.

This theory is put to the test when Milk’s wife Iris sleeps with another member of Kinsey’s inner circle. Milk soon understands that accepting infidelity in principle and consenting to it in practice are different things, especially when one’s beloved spouse is involved. Instead of the pioneer, mapping new regions of sensual experience, he feels more akin to “the stooped demeaning figure of the cuckold in the commedia dell’arte”.

The movement from idealism to disenchantment is characteristic of all Boyle’s fiction; here it reaches its grim conclusion when Kinsey and Milk discover Mr X, a subject of legendary sexual accomplishments. Their interview with him turns from jolly prurience into grisly nightmare when the man reveals himself to be a pederast, utterly unrepentant and proud to display photographs of his crimes. After this, Milk finds it impossible to subscribe without reservation to Kinsey’s belief that “man was pansexual, and it was only convention — law, custom, the church — that kept him from expressing himself with any partner that came along, of whatever sex or species”. The zoologist might feel able to dispense with romantic love: simple evil, it seems, is less easily explained away.

That said, Boyle’s portrait of the scientist remains rich with comic nuance. Whether he’s drumming up 1,000 men to masturbate on camera or arranging a screening of a rare film of mating porcupines, Kinsey’s boundless enthusiasm is hard not to admire. His message of tolerance, “to bring human sexuality out of the dungeon to which the priests had confined it and to celebrate it, glory in it, experience it to the full, without prohibition or inhibition”, is particularly timely in these reactionary days. For every Mr X, after all, there were tens of thousands of lonely housewives and gay men who could take comfort in the numbers Kinsey crunched, the unassailable scientific proof that, no matter what the dungeon-guarding priests might say, they were not alone.

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