Geographically speaking, any high-purity Number Four heroin that appeared on Hong Kong Island could almost certainly be traced to the Golden Triangle.
The Golden Crescent was far away in Afghanistan. An overland route would have to pass through the world's forbidden zone for drugs, while a sea route would involve an enormous detour.
The remaining source, the Silver Triangle, was in South America, separated from Hong Kong Island by the vast Pacific Ocean.
Shipping Number Four heroin into Hong Kong Island from the Golden Crescent or the Silver Triangle simply was not worth the cost.
Not only would the risks multiply, but the eventual profits would also shrink considerably.
As mid- to senior-ranking officers in the Security Department, He Wenzhan and Yeung Kam Wing immediately identified the suspicious connection to the Golden Triangle.
A situation this serious was already beyond their authority to handle. They had to report it to their boss.
Still, both men had handled numerous major cases and had considerable composure.
He Wenzhan remained seated, his face expressionless, while Yeung Kam Wing continued taking notes.
With tacit understanding, they maintained their calm presence, backing up their boss's First Disciple.
After all, Guan Zu had only joined the Police Force a few months ago and could not yet consider matters that far ahead.
He continued at his own pace, handling the case of the Xinglong Triad Society's involvement in drug crimes.
"Sir Lau, could I trouble one of your men to invite that gentleman back in?"
Turning his gaze toward Liu Jinkui on his right, Guan Zu made the request politely.
Guan Zu had never been concerned about Tam Chung-yiu's claim that there was no evidence.
As long as they caught Cha Zha, whom Tam Chung-yiu had mentioned, they could follow the trail to Yim Sai Kau and