There was one land, however, which was whole early on. Tucked away high in the Himalayas, its neighbours snapped at it but took only small morsels. All but self-contained, adopting a form of tantric Buddhism, an air of mystery surrounded the Tibetans. Every monastery had at least one monk from each family. Their abbots were high lamas, selected by reincarnation and passing certain tests.

It wasn't until the 20th century that Britain set its boundaries and China put in their claim. What brought Tibet to global attention between the two World Wars was a novel by a Brit who set it there but gave it another name. James Hilton called it Shangri-la. The stories he picked up about Tibet, combined with his imagination, made Lost Horizon a classic.

Open to tourism now, a rail-line constructed to Lhasa, the capital, the theocratic ruler the Dalai Lama in self-imposed exile in India, Beijing insists it's part of China. Still, the age-old mysticism remains. Authors remain fascinated and a number have penned their own works of fiction. Yet none has captured the popular fascination that Hilton had.

The team of Douglas Preston and Lincoln Child add to the genre with The Wheel of Darkness. They've pulled out all the stops in this tale of an invaluable reliquary containing the Agozyen, stolen from the monastery of Chongg Ran. Its protectors never saw it during the millennia it was in their possession, there being a warning that it would blow the minds of those who did.

Fortuitously special agent Aloysius Pendergast, the writers' literary creation, has been spending his annual holidays from the FBI at Chongg Ran, studying meditation. This time he's accompanied by his ward, Constance Greene. Knowing who the culprit is, a Yank who had recently showed up, our hero figures the pursuit won't take long.

The beginning and end of the book is set in Tibet, in between on a luxury liner after a brief stopover in London. The reliquary is onboard the Britannia, bigger and better and safer than the Titanic nearly 100 years before. And the reliquary has changed hands through murder. Pendergast and Constance are among the passengers, New York the destination.