Ancient and modern: India at 50

Michael Arditti takes a taboo-breaking tour of the underworld: The Invisibles by Zia Jaffrey, Weidenfeld & Nicolson, pounds 15.99

In 1984, Zia Jaffrey travelled from America to Delhi for a family wedding. She was astonished to discover the uninvited but tolerated presence of the hijras (eunuchs), who sang raucously, mimicked childbirth, insulted the guests and were paid handsomely for their pains. Her wish to learn more about this ancient tradition was discouraged. Instead, she was advised to "study something useful, like our urban development planning". Fortunately, stubbornness prevailed.

The result, 12 years later, was The Invisibles, which might have been titled The Unknowables. Although Jaffrey undertakes a fascinating voyage around the hijras, much about them - from their development to their current strength, variously estimated at between 25,000 and 1,250,000 - remains a mystery. Despite the apparent openness of a particular eunuch "family", their revelations are carefully guarded. They are happy to discuss the more socially acceptable aspects of their lives (their presence at weddings and after childbirth) while categorically denying any murkier practices: kidnap, mutilation and prostitution.

The Invisibles, appropriately for its subject, is a hybrid. The quest for the hijras provides Jaffrey (and the reader) with the opportunity to discover India. She describes herself as born with "that spiritual wishy-washiness" of being neither Indian nor American. The "otherness" of the hijras mirrors her own. Her aunt warns her that to study the eunuchs will make no man want her; the subject is so taboo in polite society that she is ushered out of a party when she broaches it. On the other hand, friends and contacts go out of their way to help her, battling with an inefficient bureaucracy.

One part of Jaffrey's scheme is to provide a historical perspective on the hijras. She is told that in contemporary hijra society "all castes are represented ... Hindu and Muslims alike". Their origins are, however, more contentious. They are mentioned in the ancient Hindu epics, the Mahabharata and the Ramayana. It is probable that the tradition, which flourished in North India, derived from Hinduism and grew in prominence under Islam.

Jaffrey quotes Western observers from Marco Polo onwards on the role of eunuchs under the feudal rulers. Some commended their loyalty, most denounced their barbarism and servility. She notes the British attempt to destroy their privileges as part of the policy of ridding India of her "debased oriental practices". In the event, all they did was to drive the hijras from the countryside to become part of the urban underclass, which the British largely ignored.

Her exploration of this underclass constitutes the most engrossing sections of the book. She provides a gruesome eyewitness account of a castration ceremony, where a boy is made to sit on a thickly oiled wooden phallus prior to having his testicles removed. Other sources tell of the hijras cutting off their own penises (which palace eunuchs had to produce, pickled in jars, as proof of their impotence). One common way for the hijras to extort money is by threatening to expose themselves; another is by threatening to expose the impotence of married men. They have the licensed raillery of Shakespearean fools, witnessed when they sing at the birth of the first child (after 12 years) of a Hyderabad businessman and name the boy as the son of the family's cook.

In the last resort, there is a sadness about the hijras, exemplified for Jaffrey when she returns to India after 10 years and finds the original "family" who befriended her in ruins. Indian society is ordered around families. Excluded from ordinary families, the hijras create an alternative, grouped around a guru, but it is one born of desperation rather than freedom. The self-mutilation is the antithesis of any exploration of sexual ambiguity that might be welcomed in the West.

This is a lucid, sympathetic and unsensational exploration of a unique phenomenon. At the end, one of Jaffrey's correspondents writes that he hopes that "you will be fair in dealing with the subject, so that it may not hurt the feelings of any caste or creed or person". It is a hope which she has admirably fulfilled.