Collins Chinese Dictionary Plus (3rd edition), 2011:
暗中 ànzhōng
I 名
the dark
- 我在暗中什么(麼)也看不见(見)。 Wǒ zài ànzhōng shénme yě kànbùjiàn. I couldn't see anything in the dark.
II 副
surreptitiously
- 他暗中操纵(縱)选(選)举(舉)。 Tā ànzhōng cāozòng xuǎnjǔ. He surreptitiously fixed the election.