The play's centerpiece is a deception scene in which two men manipulate Elektra with lies to a point of near hysteria. She is an adult but unmarried female in the house of a mother who hates her and she has neither social function nor emotional context. She seems to squat on the doorstep of the house rather than live inside. Her sister calls her a maniac and waves her ideas away. Her brother treats her as superflous to his plans - he finds her wild, emotional, depressing. She is a woman stranded at doorways and passivity is killing her.
There is only one thing she can do.
Anne Carson sobre Electra in Sophokles, "Elektra", An Oresteia, Faber & Faber, 2009.