We meet with two specialists at the forefront of ninja research. In 2021, Fukushima Takamasa found the Kanrinseiyo. Known to exist but never seen before, it's said to be the source material for the famous ninja manual, the Bansenshukai. It reveals previously unknown information about the ninja, including group tactics, night infiltration methods and a new ninja tool. We also learn about the ancient manuscripts Professor Yuji Yamada discovered at the Library of Congress in the US.