During the War of Resistance Against Japanese Aggression, the Kuomintang negotiated cooperation between the Kuomintang and the Communist Party while also asking their Ministry of Defense to secretly formulate a plan for attacking the Communist army, codenamed "A-14". Unexpectedly, Japanese spies stole this plan in a vain attempt to blackmail the Kuomintang into defecting to Japan. The Ministry of National Defense immediately organized a "Black Phoenix" operation to recapture the "A-14" plan, and sent officers under the pseudonym "Black Eagle" to carry it out.
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