King Lear Act 2, Scene 1
Gloucester is informed that Regan is en route with Cornwall and expected that evening. He hears the recent rumors that there are increasing divisions separating the Albany and Cornwall blocs. Once Edmund hears that things are about to get hectic, he decides that this would be the ideal opportunity to further his case against his brother.
Once Edgar appears, Edmund acts like things are dire. He tells Edgar that Gloucester has posted guards around and is searching for Edgar. Also, Edmund asks, could it be that Edgar has derided Cornwall, who is headed into town, or even Albany? Edmund tells his brother he can hear Gloucester's footsteps and convinces his brother to have a fake duel with them and then flee quickly.
The fake duel will give Edmund the opportunity to injure himself and then blame the injury on his brother. Gloucester enters the stage with his servants and asks Edgar's whereabouts. Edmund stalls because he wants his brother to get out of range, so the story doesn't end too quickly. Once he feels his brother has gotten far enough, he sends Gloucester after him, in what it seems is the wrong direction.
He then tries to convince Gloucester of his brother's cruelty. He claims Edgar asked him to join his "unnatural purpose" (line 50), but he opposed, and the brothers duelled. Gloucester needs no more convincing that Edgar has gone bad, and decides he will search everywhere for Edgar to both capture and punish him. Most importantly, he is so impressed with Edmund's loyalty to the family honor that he declares his son will be "legitimized" and thus become the heir.
Good things have happened for Edmund faster than he had expected. But before things continue, Cornwall and Regan appear with an entourage of servants in tow, indicating how grand they have become.
Regan quickly says she has received news of Edgar's villainy and has come to repudiate her father's (Lear) naming of Edgar as his godson. The two stories are converging here.
"What, did my father's godson seek your life?
He whom my father named, your Edgar?" (lines 91-92)
Regan, not thrilled with her father in the least , suggests that Edgar has been surrounded with bad people, spending so much time with Lear's posse. Edmund, without hesitation, confirms her suspicions.
Regan, once again, uses the opportunity to lash out further against her father and his knights. She says that if Lear were to arrive at that very moment, he would find discomfort in her distant reception.
Cornwall is so impressed by Edmund that he asks him to join his own faction, praising his "Natures of such deep trust..." (line 115).
Regan then seeks to attract Gloucester to her cause against Lear. She tells him she trusts his friendship and advice so much and that she needs help deciding what to do with the separation between her father and her sister, Goneril. Yet it seems clear throughout this passage that although she has heard cases from both her father and her sister, she has been "well informed" by Goneril and wishes to make a case against her father, clearly taking the side of her sister.