Back at Gloucester's former palace, widowed Regan questions Oswald about Goneril and Edmund. She pauses to explain that Edmund himself has gone to kill Gloucester—whose pitiful appearance, blinded and wandering, is turning the people against the British—and to also assess the power of the French army. Then, she resumes pestering Oswald, asking him to open the letter that he is carrying from Goneril to Edmund and let her read it. Oswald refuses, but Regan insists that he take the following news to Goneril: Cornwall is dead, Edmund and Regan have spoken and concluded that it is more convenient for him to marry Regan than her sister.
Presumably, Regan desires Edmund both as a sex-object and as a protector of her political power, now that she is a widow. Her persistent selfishness, which led her to abuse her father, will now erode her bond with her sister, with whom she has been united up to this point.
Regan concludes by saying that she will show favor to whoever kills "that blind traitor" (41), Gloucester.. Oswald responds that if he runs into him en route to Goneril, he will kill Gloucester. Then Oswald rushes off.
Regan's command to kill Gloucester reveals her real brutality. Oswald shows the blind willingness to obey in order to ingratiate himself with powerful people, exactly the trait for which Kent mocked him in 2.1.