Castle summary: "Castle", South Korea's omnipotent crime syndicate. One man returns to Korea in order to topple the absolute stronghold that is "Castle". Kim Shin, the Korean-born Russian killer named "Amur Tigro". He comes back to the crime-ridden city of Hoe-Am in accordance with the last will of his mentor, Kang Min Sung. Kim Shin and his comrades put their lives on the line as they head for the final showdown…