Search for rare dolphins an unlikely thriller

The Hungry Tide
By Amitav Ghosh
Houghton Mifflin, 333 pp., $25

It is the most unlikely of novels to be described as a thriller. The setting is not Monte Carlo or Istanbul. Rather, Amitav Ghosh's gentle, subdued new novel, ''The Hungry Tide," is set in the mangrove swamps of the archipelago of the Sundarbans, off the eastern coast of India. Its two main characters are an Indian-American cetologist searching for endangered Orcaella dolphins and a successful young man who works as an interpreter in New Delhi, and despite the sexual tension between them, nothing much happens. Apart from a scene that features a cyclone, most of the dramatic events described in the book occur offstage, shrouded as they are by the passage of time.

And yet, ''The Hungry Tide" is a certifiable page-turner. Blending fact and fiction, history, and imagination, Ghosh tells the gripping story of two strangers who come together in the remote town of Lusibari. Piya, who lives in Seattle, has come to study the marine life of the Sundarbans. Kanai has been summoned to Lusibari by his elderly aunt, Nilima, who wants to bequeath to her nephew her dead husband Nirmal's newly discovered diaries.

Kanai's interest is captured by Nirmal's journal, especially its telling of the bloody clash in 1979 between the Indian government and the desperate refugees who had illegally occupied and settled the village of Morichjhapi. Ghosh skillfully uses the true story of the siege of the village as a background for an unlikely and poignant romance that develops between the retired schoolteacher Nirmal and the object of his desire.

That long-ago romance, now only accessible to Kanai in the pages of his uncle's journal, lives anew in the nebulous triangle that unexpectedly develops among Kanai, Piya, and Fokir, the mysterious, almost mystical fisherman who saves Piya's life and becomes her guide through the tiger- and crocodile-infested swamps of the Sundarbans. Ghosh subtly describes the deep, unspoken bond that develops between the American outsider and the impoverished fisherman -- a bond that echoes the middle-class Nirmal's attraction for a poor Morichjhapi woman. He is also adept at convincing us that the gap between the established, settled Kanai and the wandering, gypsy-like Piya is equally unbridgeable, despite their shared middle-class backgrounds.

Ghosh takes his time in setting Piya, Kanai, and Fokir off on a boat together -- Fokir acting as her guide, Kanai there to act as an interpreter between Piya and Fokir. Such is the power of Ghosh's precise, understated prose that one occasionally wishes to turn the pages three at a time, eager to find out where Ghosh's tale is headed.

Perhaps there is also another, less charitable reason for this haste: Kanai, the nominal hero of the book, is a tough sell because he is a surprisingly flat character. A self-described ladies' man, he comes across as a blowhard at times and clueless at others. His dialogue is strangely emotionless, so that often he seems to be simply acting as a foil for the other characters to say their piece. An example:

''So what happened after that?" Kanai said. ''Where did she go?"

''She didn't go anywhere, Kanai. She was killed."

''Killed?" said Kanai. ''How? What happened?"

In any case, the story gathers momentum once the three of them set sail in search of the Orcaella dolphins. From this point on, the novel becomes a good, old-fashioned adventure story. The tigers that prowled the Sundarbans and dominated the mythology and legends of the islands suddenly stage an appearance.

Ghosh's description of the cyclone that hits the area -- alternating between the fate of Piya and Kanai, who have gone their separate ways -- is nothing short of masterful and reminiscent of the famous hurricane scene in Zora Neale Hurston's ''Their Eyes Were Watching God."

The novel ends with an epilogue that some may find gratuitous but that feels satisfying to this reviewer. Given Ghosh's minimalist prose and understated emotions, ''The Hungry Tide" leaves one -- well, hungry, for more of an emotional connection. The epilogue feels like a satisfying dessert after a main course that is nourishing, beautifully presented, but small-portioned.

Thrity Umrigar is the author of the novel ''Bombay Time" and the upcoming novel ''Thicker Than Water." She lives in Ohio.