Continuing her journey from a deeply religious Islamic upbringing to a post at Harvard, the brilliant, charismatic and controversial New York Times and Globe and Mail #1 bestselling author of Infidel and Nomad makes a powerful plea for a Muslim Reformation as the only way to end the horrors of terrorism, sectarian warfare and the repression of women and minorities.

Today, she argues, the world's 1.6 billion Muslims can be divided into a minority of extremists, a majority of observant but peaceable Muslims and a few dissidents who risk their lives by questioning their own religion. But there is only one Islam and, as Hirsi Ali shows, there is no denying that some of its key teachings—not least the duty to wage holy war—are incompatible with the values of a free society.

For centuries it has seemed as if Islam is immune to change. But Hirsi Ali has come to believe that a Muslim Reformation—a revision of Islamic doctrine aimed at reconciling the religion with modernity—is now at hand, and may even have begun. The Arab Spring may now seem like a political failure. But its challenge to traditional authority revealed a new readiness—not least by Muslim women—to think freely and to speak out.

Courageously challenging the jihadists, she identifies five key amendments to Islamic doctrine that Muslims have to make to bring their religion out of the seventh century and into the twenty-first. And she calls on the Western world to end its appeasement of the Islamists. "Islam is not a religion of peace," she writes. It is the Muslim reformers who need our backing, not the opponents of free speech.

Interweaving her own experiences, historical analogies and powerful examples from contemporary Muslim societies and cultures, Heretic is not a call to arms, but a passionate plea for peaceful change and a new era of global toleration. In the wake of the Charlie Hebdo murders, with jihadists killing thousands from Nigeria to Syria to Pakistan, this book offers an answer to what is fast becoming the world's number one problem.