A police detective reconnects with people from an undercover assignment in her distant past in order to make peace.
The plot is devoted to the history of Los Angeles detective Erin Bell (Nicole Kidman), in her youth working undercover in one of the Californian criminal gangs. Then the mission of the heroine ended in failure, and after many years the leader of the underground organization reappears on the horizon and finds Bell (now a seasoned and ruthless woman), forcing her to return to the old cause.
Destroyer follows the moral and existential odyssey of LAPD detective Erin Bell who, as a young cop, was placed undercover with a gang in the California desert with tragic results. When the leader of that gang re-emerges many years later, she must work her way back through the remaining members and into her own history with them to finally reckon with the demons that destroyed her past.