About Kurosawa film, "7 samurais."

Kanbei, played by Takashi Shimura, the leader of 7 samurais finds the weak-point of the village that they should defend. He says, "Nice. It's very nice. Any good catsle has ONE weak-point."

Enemy atacks its weak-point, and the samurai-warriors in the castle intercept at the weak-point.

Vulnerability is feed, and Castle itself works as a trap.