水落石出 -------- The truth will out

例句：
A: How come the murder happened?
那宗凶杀案是如何发生的？
B: Who knows? But the police are looking into it, and I think the truth will out soon.
谁知道？但警方正在调查，我认为不久就会水落石出。

同义词：
be brought to light
come out in the wash;
murder is out
Truth lies at the bottom of a well