It gets under your skin, because the hunt never stops long enough for you to relax either. Kamui walks away from his clan and the show refuses to give him a single safe night for it, and by the middle of the run his paranoia isn't a plot device, it's the honest cost of being hunted by people who used to be family. Sanpei Shirato's gekiga blood is all over it: ninjutsu treated as brutal physical craft rather than magic, peasants and outcasts drawn with real class anger, nature as indifferent as any assassin. This is 1969, and it already built the deserter-ninja template that decades of shonen would strip-mine and sand down. The animation is spare, but the loneliness is not. You come for the escape artistry and leave gutted by a man who can beat every pursuer except the suspicion in his own head.

Kamui is a ninja of Japan's Edo period who climbed out of the downtrodden peasant class, then chose to leave his clan. The decision brands him a traitor. His former clan members hunt him relentlessly across the country, determined to kill him. Now a fugitive, Kamui relies on his intelligence and considerable skills to stay alive as he wanders Japan. Over the course of his flight, the constant threat takes its toll. Paranoia sets in, and Kamui comes to believe that everyone he meets wants him dead, leaving him unable to trust anyone.