Since ninja were engaged in espionage, they had to gather information and accurately convey it without anyone knowing. Typical means of information transmission included smoke signals, a cipher using knots in a rope, and special methods of transporting secret messages. But in the second half of the episode, we'll look at their ultimate method of concealing information: invisible ink! Find out how they did this, and follow Chris as he makes his own secret message with ninja techniques.

The Hojo clan was a warrior clan that ruled the Kanto region from the 15th to 16th century. Supporting their efforts to defeat enemies and maintain control was a mysterious group called the Fuma ninja. Their leader, Fuma Kotaro, is described in historical documents as a monster, and may have been the reason why they were so feared. We'll look at how the Fuma ninja took over castles and also guarded them for the Hojo clan.

While the ninja moved unseen throughout Japan, Iga, in present-day Mie Prefecture, has been called the birthplace of the ninja arts. Join Chris Glenn and Professor Yuji Yamada as they explore Iga and trace the Iga people's journey from armed farmers who absorbed Shugendo teachings to their emergence as ninja. In the latter half, they visit sites related to the Tensho Iga War—an event that won the Iga ninja nationwide acclaim—and explore the shadow tactics used by the ninja to strike terror into the numerically superior Oda army.