JACK What are you doing down here?
When he moves to the table he is bathed in shining light that ghosts him wildly. He has a new manner, light, cheerful, drugged by single-minded madness, he is reverting, like HAL in his death throes. His consciousness is ebbing. We are now looking at only a part of Jack, who is trapped in the Overlook's mirror, his two sides unable to connect.