劈头盖脸 is a four-character idiom meaning 'right in the face' or 'directly and forcefully'. It's used to describe a sudden, overwhelming verbal or physical attack — like being scolded or hit without warning, with the force landing straight on your head and face. The literal image is 'splitting the head and covering the face', but in modern Chinese it's almost always figurative, especially for harsh criticism or a barrage of questions.