Cordell Walker, a widower and father of two with his own moral code, returns home to Austin after being undercover for two years, only to discover there's harder work to be done at home.

Cruz Manuelos, a rough-around-the-edges but passionate young Marine, is recruited to join the CIA's Lioness Engagement Team to help bring down a terrorist organization from within. Joe, the station chief of the Lioness program, is tasked with training, managing and leading her female undercover operatives.