A member of the Chinese Communist Party goes to study in North Korea, where he gets to learn about juche, the official state ideology of North Korea and the political system based on it.
The Chinese Communist Party member wishes to let his friends back home know what life in North Korea is like.
However, he knows for sure that all the letters he sends are opened by the North Korean authorities, so he thinks of a way to bypass censorship.
The Chinese decides to write words meaning precisely what they say in blue ink, words conveying neutral meaning in black ink, and words intended to convey the very opposite meaning in green ink.
After a while, his friends back home in China receive a letter from North Korea. The letter was written entirely in black ink, meant for words carrying neutral meaning.
The conclusion they draw is that North Korea is not as good as the North Korean authorities’ propaganda says it is, and it is not as bad as the critics of the North Korean regime say it is. However, at the bottom of the letter, they come across a note from their friend: “My friends, I apologize. Green ink is unavailable here….”