It's an image that haunts Khaled Hosseini, the Afghan-born author whose debut novel, "The Kite Runner," has become an international best seller. A burqa-clad woman is led into a Kabul sports stadium and shot in the head by a Kalashnikov-toting soldier. The grainy video footage, secretly recorded in 1999 and broadcast widely, captured the Taliban regime's brutality and stirred Hosseini's curiosity. "What do we really know about the woman behind the veil?" asks Hosseini, sitting at his kitchen table in San Jose. "What are their inner lives like? What are their thoughts? What are their hopes and dreams?" Hosseini, 42, explores those questions in his highly anticipated second novel, "A Thousand Splendid Suns," which follows the lives of two women who endure unspeakable loss and hardship through four decades of war-ravaged Afghan history. The novel, which has received strong, early reviews, comes out Tuesday, when Hosseini begins a seven-week book tour. It promises to be quite different from his first tour when, he recalls, he was a little-known writer showing up to speak at nearly empty bookstores. A polite man with a friendly smile, the physician-turned-novelist is dressed in jeans, black T-shirt and tan baseball cap as he gives a tour of his home office, where books crowd the shelves and drawings by his children, ages 4 and 6, are tacked on the wall. From the dark wooden desk where he writes on his computer, he has a beautiful view of the dry, grassy hills beyond the backyard of his two-story house. Yet - to his wife's chagrin - he prefers to keep the shutters closed and room dark. "It gives me that feeling of being in a bunker," Hosseini says with a grin. "It helps me isolate myself with the story and just focus and not get distracted." With "A Thousand Splendid Suns," Hosseini wants his readers to lose themselves in the novel's story and characters. But he also hopes they can gain some understanding of the struggles of Afghan women who live in a male-dominated society where they are routinely denied freedom, opportunity or dignity. "A Thousand Splendid Suns" has a tough act to follow. "The Kite Runner," the story of two boys growing up in Afghanistan before the Soviet invasion that led to two decades of political upheaval and civil war, is a publishing sensation. Released in hardcover in 2003, the novel quickly took off after it became a favorite of independent book stores, book clubs and community reading programs. It spent 114 weeks on The New York Times best seller list, and its paperback edition remains on best seller lists. Nearly 5 million copies of "The Kite Runner" have shipped in the U.S. alone, and the book has been translated and published in more than 30 countries, according to publisher Riverhead Books, a division of Penguin Group USA. A movie adaptation, filmed in western China and produced by DreamWorks and Paramount Pictures, is expected to be released later this year. "A Thousand Splendid Suns" has been eagerly awaited by readers, booksellers and, of course, its publisher, which is launching a major campaign to promote what it expects to be one of its top sellers this year. "When I took the manuscript home, I was so nervous," said Penguin President Susan Petersen Kennedy. "Your hopes are very high, but most of the time the second novel is not as surprising or moving. It usually doesn't have the same punch as the debut." But those worries were put to rest, she says, after she read "A Thousand Splendid Suns," whose title comes from a phrase in a 17th-century Persian poem. "When I was reading it, I was crying, I was haunted, I couldn't talk to my family," she says. "The book is brilliant. I think it will sell enormous numbers of copies." Amazon.com has been an early supporter. The online retailer offered an exclusive prepublication excerpt from the book and sent copies to several of its top reader reviewers, who posted their highly favorable responses. Well before the novel came out, "A Thousand Splendid Suns" was in the top 20 of Amazon.com's best seller list. "It was very grass roots," says Amazon's director of merchandising, Laura Porco. "A very early manuscript version came to us from the publisher. One of our buyers loved it and passed it on, and we all fell in love with it. We felt it was a book that would resonate with our customers." Judy Wheeler, who owns Towne Center Books in Pleasanton, Calif., was similarly moved by Hosseini's second novel and liked it more than his first, partly because the protagonists are women. "The book clubs will love it because there's tons to talk about," says Wheeler, who ordered more copies after reading it in two nights. "It's going to sell really well." "A Thousand Splendid Suns" shares common themes with "The Kite Runner." While the first novel follows the friendship between two boys of different ethnic groups and social classes, the second chronicles two women of equally contrasting upbringings - Mariam and Laila - who forge an improbable bond to survive. "Both are stories of unlikely love," Hosseini says. "In both novels, it's this unexpected love that redeems the characters and gives them the strength to be good, selfless and noble." The son of an Afghan diplomat, Hosseini didn't experience most of the tumultuous history that pervades his latest novel. His family left Afghanistan to live in Paris in 1976, when he was 11. In 1980, after the Soviet invasion, they moved to Northern California, where he attended high school and later studied medicine, from which he took a leave two years ago to concentrate on writing. The novel's main characters are not based on any women he knows, but they are partly inspired by the stories he heard on the streets of Kabul during his first trip back to Afghanistan in 2003. "I began to understand the devastating effect that anarchy and oppression had had on these women," Hosseini says. "I heard about women who had been raped, attacked, humiliated and imprisoned. I heard about women who had seen their husbands blown up, their children starved to death, who had to make these incredibly difficult choices." Hosseini says writing the second novel was much more difficult than the first, in large part because he was under contract and deadline and so many people were expecting it. "You want to show the world you're not a hack," he says. "More importantly, you want to show yourself you're not a hack, that it wasn't just a fluke or accident, that you really do have something to say beyond just your first book." But those worries faded once he started writing and fell in love with the story and characters. Hosseini, a self-described perfectionist who agonizes over his prose, wrote the book in five drafts over two and a half years. One of the biggest challenges was writing about women from a female perspective. He says he often consulted his mother, sister and other female relatives. His wife Roya, an attorney who is also of Afghan descent, acted as his primary editor and let him know when the story didn't ring true. While he will always love "The Kite Runner," which he likens to a first-born child, Hosseini says he gained a deeper sense of accomplishment when he finished "A Thousand Splendid Suns," which he considers a more mature, complex work. "I feel like I came into my own as a writer more with this novel," he says. "I love the writer's life. I used to daydream about what it would like to be a writer who writes for a living. Amazingly enough, I'm living that life now."