粵典 (words.hk)香港詞
喺背後，唔俾人察覺咁指揮或者操縱一切（量詞：個） (the master-mind, the power behind the scenes)
名詞用例
過咗十年，警察終於查到呢單兇殺案嘅幕後主腦係邊個喇！
gwo3 zo2 sap6 nin4, ging2 caat3 zung1 jyu1 caa4 dou2 ni1 daan1 hung1 saat3 on3 ge3 mok6 hau6 zyu2 nou5 hai6 bin1 go3 laa3!
After 10 years of investigation, the police can finally figure out the man behind this murder case.