Revelatory. * Simon Heffer, Books of the Year 2018: History, The Daily Telegraph *
A history book that will surely inspire future fiction. A work of deep scholarship and clever detective work. * Leanda de Lisle, Books of the Year 2018, BBC History Magazine *
A dense, hugely researched and admirably learned history of women spies during the Civil War. * Dominic Sandbrook, The Sunday Times *
A brilliant book. * Noel Malcolm, The Sunday Telegraph *
A triumph of scholarly rigour, original thinking and crisp prose. It is, in every sense, a cracking book. * Jessie Childs, The Daily Telegraph *
Invisible Agents is a work of deep scholarship that suggests Akkerman would have made an excellent spy catcher. * Leanda de Lisle, The Times *
Brimming with fascinating detail ... Akkerman's archival dissections admirably emulate the painstaking vigilance of early modern spy masters. * Clare Jackson, The Times Literary Supplement *
Pioneering ... a most valuable book, highlighting women's contribution to the conspiratorial world of mid-17th-century Britain, while also offering a thought provoking exercise in gender and historical methods. * Ann Hughes, BBC History Magazine *
An intriguing book ... [Akkerman's] own remarkable ability to ferret out secrets is often as great as that of the spies she writes about. Time after time, women whose lives, careers and even names have been forgotten or misread spring into stealthy, double-dealing life on the page. * Adrian Tinniswood, Literary Review *
Invisible Agents breaks significant new ground in its focus on the special roles of Royalist and Parliamentarian 'she-intelligencers' and their hidden world. This is a model monograph, meticulously researched and relentlessly questioning, which succeeds admirably in uncovering closely guarded secrets. * R. C. Richardson, Times Higher Education *
This is a book full of rich and engaging details...this is a testament to the thoroughness of her academic practice. Ultimately, Invisible Agents is a text that serves as an invaluable starting point for the re-situation of women into narratives of early modern spying, and political history, offering readers across disciplines a varied and voluminous history of women's roles in seventeenth-century espionage. * Rose Hilton, AC Review of Books *
A ground-breaking book looking at a previously unexplored aspect of the world of espionage ... Founded on work in a wide variety of archives, many of them previously undiscovered, Akkerman shines a light on one of the dark corners of the world of spies. * Military History Monthly *
For a serious examination of the role of women in intelligence, turn to Nadine Akkerman's Invisible Agents. Doubly invisible, both as agents and in historical records, these women were at the heart of the intelligence network, yet they have never hitherto received the 'glory of Martyrs'. * Teresa Levonian Cole, Country Life *
Fascinating and insightful ... Akkerman lifts the veil not only on a number of individual she-intelligencers, but also on the complex and varied business of female espionage in mid-seventeenth-century Britain. * Lena Steveker, English Studies *
Akkerman deftly handles the challenges of writing about [female spies], assembling fragments of evidence where she can, acknowledging gaps where she must. Her book has much to teach us not only about espionage but about the creation of historical narratives. * Rachel Weil, American Historical Review *
A dazzling study of a truly neglected subject, which ably demonstrates the gendered dimension of early modern spy-craft, and the unique ways in which women were able to operate. It is written by one of the foremost early modern textual-historical scholars of her generation and marshals an almost unmatched expertise in working with an impressive range of European and international archives of the period. The book delivers a series of fascinating case studies - including Charles I's prison correspondence, Secretary Thurloe, as well as female practitioners Susan Hyde, Elizabeth Murray, Elizabeth Carey, Anne Halkett, and Aphra Behn - all of which rest on a remarkable and overwhelming weight of archival research. This is an important book that will be widely read and cited, and which will have significant impact on many fields not least those of early modern gender and women's writing, but also political and diplomatic history. * Professor James Daybell, University of Plymouth *