Gloucester speaks with Edmund. He first complains of Cornwall and Regan taking over his house, but then discloses to Edmund, on a pledge of silence, that Cornwall and Albany are headed for war, but that the King’s injuries will be avenged (surely by an invasion from France), a threat he has confirmed in a letter locked in his closet. Gloucester leaves to find Lear. Edmund gloats at his good fortune, and promises to tell Cornwall everything to further his aim of dispossessing his father.
ACT III. SCENE III. At Gloucester’s house.
Enter Gloucester and Edmund.
Alack, alack, Edmund, I like not this unnatural dealing. When
I desire their leave that I might pity him, they took from me the
use of mine own house, charged me on pain of their perpetual
displeasure neither to speak of him, entreat for him, nor any way
sustain him. 
EDMUND Most savage and unnatural!
Go to. Say you nothing. There’s a division betwixt the dukes,
and a worse matter than that. I have received a letter this
night, ’tis dangerous to be spoken. I have locked the letter
in my closet. These injuries the King now bears will be revenged 
home. There is part of a power already footed. We must
incline to the King. I will seek him, and privily relieve him.
Go you and maintain talk with the Duke, that my charity be not of
him perceived. If he ask for me, I am ill, and gone to bed.
ThoughI die for it, as no less is threatened me, the King my old 
master must be relieved. There is some strange thing toward,
Edmund. Pray you, be careful. Exit
This courtesy forbid thee shall the Duke
Instantly know, and of that letter too.
This seems a fair deserving, and must draw me 
That which my father loses, no less than all.
The younger rises when the old doth fall.