Luke is New Testament as I remember.
Luke 4:5-7 [5] And the devil, taking him up into an high mountain, shewed unto him all the kingdoms of the world in a moment of time. [6] And the devil said unto him, All this power will I give thee, and the glory of them: for that is delivered unto me; and to whomsoever I will I give it. [7] If thou therefore wilt worship me, all shall be thine.
Satan has dominion to do with the Earth what he will (if God permits it) until the Second Coming.
Demons are in Hell if they have been exorcised and cast there by an exorcist. But there are so many demons it makes no difference to us on Earth.