What is the 成语 for "face like buddha, heart like scorpion"?
I didn't see this film, so I am not sure if this is the original one used in the film.
From your description, I guess the idiom is &quot;人面兽心&quot;, which literally means &quot;a human's face and a beast's heart&quot;, actually is used to describe a man who looks kind, but really is vicious, evil or wicked.
By the way, I think you can show us the time point or the scene when this line appears so we can easily catch it for you.
Update:
The original word in the film is &quot;菩萨脸,蝎子心&quot;. I don't think it's an idiom. I'll treat it as an analogy, a figure of speech. Actually, &quot;菩萨&quot; isn't Buddha, but Bodhisattva, an image in Buddhism. The subtitle translated the meaning well and I think it's easy for you to understand.