Heather Miller (born: Edith Rose Sawyer) is the protagonist villain of "Texas Chainsaw 3D". She is the daughter of Loretta Sawyer and Leatherface's long-lost cousin who arrives to collect the inheritance from her grandmother Verna Carson.
The movie opens up by following the events of the first movie, The Texas Chainsaw Massacre. The Sawyer family are hiding inside their house while the Sheriff pulls up in front of the house. He demands that Drayton Sawyer comes outside and brings his son, Jed (Leatherface). When the family won't come out, a bunch of townies pull up and start to shoot at the house and eventually burns it down. Edith's mother Loretta managed to escape but was killed by a townie who picked up Edith. The townie then showed Edith to his wife, who noticed that Edith had a burn of an "S" on her chest from her mother's necklace. Edith, now known as Heather was then adopted on to the couple.
Years later, Heather has grown up and in 2012 finds out that she inherited a house in Newt, Texas. Travelling with her friends to Texas to collect her inheritance. On the way, they pick up a hitchhiker who travels with them. In Newt, Heather is met by a real estate agent who informs her that the house is now hers and that she cannot sell it. In addition to this, the real estate agent hands her a letter from her grandmother Verna Carson. Heather and her friends now go to investigate the house. While the rest of the gang travels back to town, the hitchhiker Darryl stays back at the house and starts to clean out anything valuable inside. While looking for goods, he finds a door in the kitchen and goes down to the basement. Here he finds a large metal door and as he attempts to open it, Leatherface, now known as "Jed", busts out and kills him instantly. When Heather and the gang are in town they meet the Mayor Burt Hartman, who offers to buy the house from her. Heather reclines and they return to the house where they find out that Darryl has ripped them off.
The gang decides to shake it off and while Heather's friend Nikki smokes a joint, Nikki's boyfriend Kenny cooks dinner for them all. When Kenny notices the door in the kitchen he goes to investigate and is killed by Leatherface. While the rest of the gang seem to not notice, Nikki goes up to Ryan and alerts him that there is something he has to see and the two of them go to the barn to investigate. Here, Nikki undresses and we learn that they are having an affair behind Heathers back. While Heather is now alone in the house, she suddenly sees Leatherface in the kitchen, cutting off fingers from a hand he collected. As she screamingly runs outside, Leatherface follows her while yielding his chainsaw. Heather attempts to hide inside a coffin in the Sawyers graveyard but Leatherface finds her and tries to cut her while inside the coffin. As Ryan and Nikki hears the chainsaw they run out of the barn, both half-naked. They see Leatherface in the distance and yells at him, only to panic when they see him running towards them with his chainsaw. The two of them run into the barn and as Ryan tries to lock the door, Nikki finds a shotgun. She shoots at the door but is not sure that she hit Leatherface. Suddenly they see two headlights coming at the door and the van bursts inside with Heather in the frontseat. She demands that they get in. The drive out of the barn and down to the metalgate which requires a security code in order to open. Ryan attempts to drive into the gate to get it to open, but fails and the car dies. Nikki, who is now in the backseat, sees Leatherface running up to the car and he almost gets them, but they drive through the gate. Just on the other side of the gate, the car dies again and Leatherface slashes the front tire and when Ryan tries to drive away, the car crashes.
While waking up from the crash, Nikki and Heather see that Ryan is dead. Leatherface comes up to the car and tries to kill them and cuts Nikki. Heather manages to get out of the car and lures Leatherface through the woods and into a carnival. A policeman sees Leatherface chasing Heather and holds him at gunpoint just as Leatherface throws his chainsaw at him and disappears into the woods. Heather is taken down town to the station where she is informed about the Sawyer family. When she learns that several townspeople wiped out her entire family she writes "MURDERERS" on a picture of the group of townspeople who did it. She leaves the station.
Back at the Sawyer residence a policeman is investigating the crash of the car while on the phone with the Sherif. The Sherif orders the policeman to stand down but the policeman investigates the house while sending live footage via his cellphone. The policeman notices several bloodtrails and just as he is about to leave he hears a noise coming from the freezer. He opens the freezer in one quick movement and shoots before he realizes that Nikki was inside. Back at the station, the Sheriff is accompanied by Burt Hartman, the man who was the instigator and ultimately responsible for the Sawyer family's death. The both attempt to calm down the policeman at the Sawyer residence but he is killed at the house. When the Sheriff and Burt realize that Heather is gone, Burt sets out to find her, wanting to kill her in order to protect himself and to keep the truth a secret.
After Heather leaves the police station, she meets up with the real estate agent from earlier at a bar. He explains to her that he met with Verna and Jed four months ago and that Jed had a mindset like an 8-year-old. When Burt Hartman comes into the bar Heather runs away and Burt attacks the real estate agent. Heather runs into the street and is hit by a car. She runs away and stops a police car. Upon learning that the policeman is the son of Burt Hartman, Heather is locked inside the car and is taking to the meat factory where her biological family works. Back at the police station, the Sheriff tracks the police car over a GPS system and sees that it is heading towards the meat factory. He then rushes outside.
When Heather and the policeman arrive at the meat factory, Burt Hartman and his friend Ollie is already there. They take her inside and tie her arms with rope onto two metal bars. When Leatherface arrives, he notices the scar on Heather's breast and frees her from the ropes. Leatherface is then captured by Ollie and Burt and they tie a chain around his neck. The chain slowly pulls Leatherface towards a meat grinder. While Heather is now free, she picks up a metal rake and stabs Ollie to death. She then throws the chainsaw over to Leatherface and says "Do your thing, cuz.", meaning that Heather wants him to kill Burt. While this is happening, the Sheriff shows up and holds up his gun. Heather pleads for him not to shoot and he looks away. Leatherface then removes the chain and him and Burt battle. The Sheriff takes off. When Burt falls into the grinder, he is barely holding on. Leatherface then cuts off his wrists and Burt falls into the grinder.
Heather and Leatherface travel back to the house where Heather cleans him up. Heather tries to take off his mask but he won't let her and he left to reburied their grandmother Verna. She then reads the letter from her grandmother which says that "it is now your turn". The movie ends with Heather putting on her Grandmother Verna's necklace and caring for Leatherface as she did. She lured her adopted parents to the mansion to have them be killed by Leatherface.
Role in Texas Chainsaw Massecre 3D
For most of the movie, Heather acts as the main protagonist but once she realizes she is related to Leatherface she leaves the role behind and begins helping him. Heather participates in the murder of true main antagonist Burt Hartman and later presumably allows Leather to kill her parents.
- Heather arguably fills the role of Drayton Sawyer in the end when she becomes Leatherface's new guardian.