Importance of the subplot in King Lear
“Why bastard wherefore base?” asks Edmund. The bitter illegitimate son resents his father and brother. He is determined to “prosper” and “grow.” Ruthlessly, he plays on old Gloucester’s weakness and persuades him that Edgar seeks his death to obtain his inheritance. Edgar, being told that Gloucester seeks his life for some reason, flees. With Edgar thus removed, Edmund now seeks to destroy his father and reports his alleged “treason” to Cornwall who removes the old man’s eyes. The bastard has travelled far and is now Earl of Gloucester. Sought in love by both Goneril and Regan, victorious in battle over Cordelia’s forces, Edmund’s future seems assured. Alas, the discovery of Goneril’s letter urging Edmund to kill her husband Albany leads to his arrest. Edgar in disguise fights Edmund, who is defending his honour and is mortally wounded – “the wheel has come full circle”. Gloucester, realising the wrong he has done to Edgar, yet joyful he is alive, dies. Edgar joins Albany in ruling the country.
So skillfully has Shakespeare intertwined the two plots, beginning in Act II at Gloucester’s castle and ending in the alliance of Edgar and Albany, that is is difficult to separate them. Gloucester, like Lear, suffers from filial ingratitude. It is in his castle that Lear is humiliated by his daughters and flees into the storm. Gloucester’s sympathy helps Lear to Dover to meet Cordelia, yet leads to his own blindness and his going to Dover for suicide.
Edgar becomes embroiled in the main plot when, disguised as a madman, he meets Lear on the heath. His destruction of Oswald, Goneril’s steward and his defeat of Edmund in the duel leading to Edmund admitting he has given secret orders for the execution of Lear and Cordelia, together with his alliance with Albany, all relate him to the main plot.
However, it is – appropriately enough – the corrupt Edmund who becomes most entangled with the main plot. Ambition drives him into Cornwall’s hands, and to his double involvement with Goneril and Regan.