From Romance of the Three Kingdoms: During the battle in Chibi, Zhou Yu decided to setCao Caoup so as to win the battle. Huang Gai courageously undertook the task. In the military meeting, Huang Gai pretended to disagree with Zhou Yu and even despised him in words. Therefore, Zhou Yu ordered to have Huang Gai beheaded. Other generals pleaded for Huang’s life, so Zhou Yu had him flogged instead. Huang Gai was bedridden after the severe punishment. This was actually a trick to show to Cai Mao and Zhang Yun, who pretended to surrender the Wu Camp. The two guys brought the false information back to the Cao Camp. CaoCao was so deeply convinced that he suffered a total failure in the Battle of Chibi.
The phrase “Zhou Yu Beat Huang Gai” has been evolved into a two-part allegorical saying later: Zhou Yu Beat Huang Gai – the punishment is appropriately given by one and willingly accepted by the other. It is used as a metaphor to mean something that both parties are willing to do.