The Heptarchia Mystica (or the Mystic Sevenfold Dominion) is a complete system of planetary magic delivered to the Elizabethan magus John Dee in 1582 through the crystal scrying of Edward Kelley. It details the angels ruling the planets and the days of the week, describes their functions and how to invoke them. Neglected by the Hermetic Order of the Golden Dawn and Aleister Crowley, the Heptarchia was eventually published in 1983 after painstaking research by the late Robert Turner, who collated the text from Dee's original manuscripts. A second edition followed in 1986. Unavailable for many years, the early editions are now collectors' items. This new third edition has been carefully revised and updated by Robin E. Cousins. The book is dedicated to the memory of Robert Turner and his wife Patricia Shore Turner and features a Foreword by Anne Turner. Copiously annotated and illustrated throughout, the work is complemented by a selection of essays by the authors on related themes.