be all at sea
Zhang erheng, a Chinese idiom, means that he can't figure out what's going on. From the legend of the plum in the Golden Vase.
The origin of Idioms
Chapter 6 of the legend of the plum in the Golden Vase: "when you see it, it's just like the second monk Zhang. You can't feel your head. You don't feel your leg joints soften and you flop down on your knees."
Idiom usage
Example: Zhou Tianhong was a little confused and asked, "why, no more positions?" Wei Wei's Fire Phoenix 107
be all at sea