Correct

黑幕

/ hēimù / 
Strokes

Definition

hidden details/dirty tricks/dark secrets

Example

As a Noun

inside story of a plot, shady deal, etc

1
Hēimù
黑幕
chóngchóng
重重

shrouded in sinister secrecy

2
Jiēchuān
揭穿
hēimù
黑幕

expose a sinister scheme; disclose the inside story of a plot