Revelation 1:18b Amen. And I have the keys of Hades and Death.
The Lord concludes verse 18 with the factual statement that he possesses the keys of Hades, or Hell, or Gehenna, and Death. The NKJV capitalizes the word Death, almost as if the idea of death was being personalized. We find Death and Hell together again in Revelation 20:13 and 14, where both are cast into the Lake of Fire.