Āẕar-Kayvān (b. 1529 or 1533; d. 1609 or 1618) and his disciples were founder of a sect in the 10^th century, which was known as “Āzarhušangiyān”. Very little is known about the historical details of Āẕar-Kayvān's life. However, based on the devotion of the Āẕar-Kayvānids to the Philosophy of Illuminative School (Ḥekmat-e Ešrāq) as well as the Ancient Iranian tradition, Āẕar-Kayvān is mostly identified by the modern scholars as a ‘Zoroastrian mystic High Priest’, who founded the “Zoroastrian Illuminative School”. He apparently came from Fārs and migrated to Mughal India during the reign of Emperor Akbar (r. 963-1014/1556–1605). The school of Āẕar-Kayvān is generally supposed to present “the Zoroastrian response” to the works and thoughts of Šahāb-ad-dīn Yaḥyā Sohrevardī (d. 587/1191) and the revival of the philosophy of “ancient Iran” in Islamic period. The present book by Farzaneh Goshtasb, who extensively has published on this subject in past years, is the first comprehensive monograph dedicated to the life, writings, and beliefs of Āẕar-Kayvān and his followers. The book contains some major chapters on the previous scholarship on Āẕar-Kayvān, on his life and works, on the relationship of the school of Āẕar-Kayvān with other religious traditions of his time, most specifically in conjunction with Zoroastrianism and Dīn-e ʾElāhī in the context of the intellectual life in the Mughal India. An extensive chapter is dedicated to the religious and mystical thoughts, cosmology, anthropology, miracle, and eschatology of Āẕar-Kayvān's school. The book contains several attachments of some major Āẕar-Kayvānid texts and a useful list of special terminologies of the book of Dasātīr, the most important tract of the Āẕar-Kayvānids.