have sinister motives
Chinese idiom, Pinyin is x ī nhu á IGU ǐ t ā I, which means that there is something hidden in the mind. It's from the second moment of surprise.
The origin of Idioms
Ling Mengchu of the Ming Dynasty wrote in his second moment of surprise: "who knows that Su Mei has a ghost in her heart. She just sighs. She is so depressed that she goes back to her house in silence."
Idiom usage
Subject predicate; predicate, attribute, adverbial; derogatory.
have sinister motives
The same origin and different current - tóng yuán yì liú