Alex Danvers

Alexandra "Alex" Danvers is a fictional government agent and a main character on the CBS television series Supergirl. She is played by actress Chyler Leigh and was introduced in the pilot episode of the show.

Overview
Alex Danvers is the eldest sibling in the Danvers family and the only natural child of Eliza and Jeremiah Danvers. She is the older sister of adopted Kryptonian, Kara Danvers. As an adult, Alex Danvers became a member of a secret government organization called the Department of Extra-Normal Operations (DEO), where she worked under director Hank Henshaw. The purpose of the D.E.O. was to monitor and contain threats of an alien nature. Alex believed that working for the D.E.O. might not only resolve the mystery behind her missing father, but also enabled her to protect her sister, Kara Danvers.