Antony Cummins holds an undergraduate degree in Ancient History & Archaeology and a master's degree in Neolithic Archaeology. In addition to working as a ninjutsu consultant for documentaries and other researchers, he has co-hosted television programs dedicated to the ninja. His previous works include In Search of the Ninja, True Path of the Ninja, The Secret Traditions of the Sinobi, and the Illustrated Guide to Viking Martial Arts. He splits his time between Manchester, England and Japan. Yoshie Minami earned a bachelor's degree in Linguistics from the International Christian University and has worked as a consultant for television documentaries about the ninja. As a translator, she has published True English (2009) and The True Path of the Ninja (2011). She lives in Saitama, Japan.