翻云覆雨（翻雲覆雨）　

◎ 翻云覆雨 fānyún-fùyǔ

[produce clouds with one turn of the hand and rain with another;(fig) given to playing tricks;shifty] 翻手为云,覆手为雨。比喻反复无常或惯于玩弄手段