In a Louisiana slave plantation run by Confederate soldiers, slaves are treated harshly and not allowed to speak without permission. Those who attempt to escape are killed and their bodies burned in a crematorium. After a failed escape attempt Eli watches as his wife is murdered and her body placed in the crematorium. A woman who had been assisting them is later brutally beaten and branded until she submits to being called Eden.
A group of new slaves are brought to the plantation. Among them is a pregnant woman whom the daughter of the plantation owner, Elizabeth, names Julia and places in the care of Eden. Julia asks Eden to plan an escape while Eden urges her to keep her head down. That evening, during a dinner where Julia and Eden are forced to wait on soldiers in the army, a shy Confederate soldier named Daniel is attracted to Julia and arranges her cabin later. When Julia tries to play on his kindness and asks him to help her he beats her for speaking to him without permission, causing her to miscarry.
In her own cabin, after being raped by the general, Eden hears a ringing cell phone.
In the modern era a cell phone ringing awakens Eden, who is actually Veronica Henley, a renowned sociologist. She is preparing to take a trip to speak at a seminar and promote her book, which is particularly hard for her because she has to leave her loving husband, Nick, and her daughter, Kennedi. She has a bizarre online meeting with Elizabeth which leaves her uncomfortable but she dismisses her feelings and cuts the meeting short.
While in Louisiana on her promotional tour, she meets her friends and agrees to go to dinner with them. In the meantime Elizabeth sneaks into her hotel room and steals her lipstick. Intending to go back home early in the morning Veronica leaves dinner in what she believes is her Uber ride but is actually a car driven by Elizabeth. Elizabeth’s husband Jasper knocks Veronica out revealing that Veronica and Eden are one and the same person.
Veronica discovers that Julia has committed suicide by hanging herself in the rafters. Enraged she tells her Eli that they must once again try to escape. The following evening after being raped by the general once again she sneaks out of her cabin and steals the general’s phone. Before she can call for helps she is interrupted by a drunken Daniel and his friend who find the phone but are not suspicious, believing it dropped out of the general’s bag. When he is alone Eli kills Daniel with a hatchet and retrieves the phone. As the phone can only be unlocked with facial recognition, Veronica goes back to the cabin to find the general and is surprised to find he is awake; the general attacks her and Eli is killed trying to protect Veronica. She manages to stab the general with his own sword and unlocks the phone, using GPS to send her location to her husband. Intending to hide the general in the crematorium she is interrupted by Jasper. Veronica lures him and another guard into the crematorium and sets fire to it, leaving the three men to burn to death as she steals the general’s horse and rides off.
Elizabeth pursues her on horseback and reveals that she handpicked every slave on the plantation except for Veronica, whom she kidnapped at her father’s insistence. Veronica knocks Elizabeth off her horse and puts a rope around her neck, dragging her until she hits a statue of Robert E. Lee, breaking her neck. Veronica flees the pursuing soldiers into the chaos of a battle, revealing that the plantation is actually part of a Civil War reenactment park owned by the general under his real name of Senator Blake Denton. Veronica escapes as the police arrive to liberate her and the other captives. The park is later razed to the ground.