at dead of night
It's a Chinese idiom. Pinyin is y è J ì NGG ē NGL á n, which means silent night. It comes from lianhuanji.
The origin of Idioms
The fourth fold of Yuan Wu Mingshi's serial stratagem: "now it's a man who is busy asking for the truth, but he's leaning against the door."
Idiom usage
As an object or attribute; late at night
at dead of night
be closely related and mutually dependent - chún chǐ xiāng xū
read several lines at one glance - yī mù shù háng
bring glory to one 's parents and become celebrated - xiǎn qīn yáng míng