Sauron, the principle villain in the Lord of the Rings films, is omniscient, and sees all, particularly the ring-bearer Frodo at times, if he slips it on his finger. In the films, Sauron is distracted, allowing Frodo and Sam to slip undetected toward Mount Doom, with Sauron only turning his watchful eye toward them after the ring has been destroyed, causing him to crumble and disintegrate. He really should have kept his contact lens on.