Itachi, with crows breaking out of the frame behind him and a Sharingan sitting above his head like a sun.
The composition is built on radiating lines — everything points outward from the centre of his forehead, so the eye keeps returning there no matter where it wanders. The clouds along the bottom are the only curves in the piece; without them the whole thing would feel like a spike.
It is a character built entirely on withheld information, so the finger over the mouth was the only pose worth drawing.