Favorite Chinese phrases?

This question is specifically for us Cdrama lovers. What's your favorite Chinese phrase or saying?

For me, it's definitely gotta be "getting your brain/head caught in the door"

Whenever the ML rescues FL he usually says " Don't be afraid, I have arrived or I am here" 

 autumn iris:

Tian fan di fu (Sky and earth turning upside down)

Shuo Cao Cao, Cao Cao dao (speak devil, devil comes)

I also like these two very much lol 

 kotatsumushi:

Not an idiom but for me:

你好的大胆子！Nǐ hǎo de dàdǎnzǐ! 

大胆！Dàdǎn!

好大的狗胆！Hào dà de gǒu dǎn!

你胆子真么大！  Nǐ dǎn zǐ zhēn me dà!

Basically, it can be said all of them means "How dare you!"

Also I like 三思而后行  (sān sī ér hòu xíng) meaning think twice before taking an action, look before you leap

these are all very good too!