Book excerpt: Traces changing visions of mystical power and authority on the island of Pemba, whose people's reputed resistance to outside rule has shaped the national narratives of both Zanzibar and Tanzania. For two centuries, Pemba, the second largest island of Zanzibar, has been known by East Africans and outsiders alike as rich in dangerous knowledge. Despite Pembans' reputation for piety and deep Islamic knowledge, uchawi- 'mystical work and power', sometimes termed 'magic', 'witchcraft', or 'sorcery' - has long featured in diverse visions of their identity and as key to worldly power. Today, as traditional methods of securing agency are called into question and new ways proliferate, the mystical world is an intensely conflicted realm where the nature of power, ethical action, and reality itself is continually reframed. This luminous ethnography follows Pemban notions of invisible and worldly power through the Zanzibar Revolution of 1964, the trials of multiparty democracy, the rise of Islamic revival, and intensifying neoliberalism. Through an exploration of rural imaginings of power, it argues that nations and the grammars that underwrite them are made in and by their peripheries, which give 'the centre' shape. Highlighting the intersections of mystical practices, religion, and politics-as-such on the Swahili Coast, the book contributes new perspectives to studies of the imagination, power, and religious transformation in Africa, the Indian Ocean, and the larger Islamic world.