画龙点睛

huà lóng diǎn jīng

to paint a dragon and dot in the eyes (idiom); fig. to add the vital finishing touch

the crucial point that brings the subject to life; a few words to clinch the point

画

huà

to draw; to paint

龙

lóng

(fig.) emperor

点

diǎn

to touch briefly; to tap

睛

jīng

eye; eyeball