You are a assasin, and you are assigned to kill an actor, you have prepared a plan for that actor, you plan to kill him from a distance.

Today, he was smoking on the roof of the building, you think that's when he let his guard down, you positioned your long-range shot at your target, your place and his place were far away. When you position your long-range shot at him, he suddenly turns towards you, as if he realizes he has been watched by you.