"Texas Chainsaw 3D" makes quick work of erasing "TCM 2" from the timeline. Instead of police being unable to find the Sawyer farmhouse after Sally Hardesty escapes, "3D" presents a full lynch mob led by Hal Hartman's son Burt (Paul Rae) and a farmhouse filled to the brim with Sawyers, including Drayton (Bill Moseley from "TCM 2"), Leatherface (Dan Yeager), and a couple of new ones played by original Leatherface Gunnar Hansen as Boss Sawyer and Dodie Brown as Sawyer sister Loretta. The mob opens fire on the house and sets it ablaze, killing all the Sawyers except for Leatherface and Loretta's baby daughter.
Some years later, Heather (Alexandra Daddario) inherits a large Texas mansion from a distant relative, but she and her friends find more than they bargained for — notably Leatherface living in the basement. As he begins mowing through Heather's friends, Burt Hartman sets out to track down Leatherface himself and get revenge for the murder of his family.
It doesn't take a genius to realize the film's big twist — that Heather is the infant who survived the farmhouse attack, and the dead relative is Verna Sawyer (played here in a cameo by Marilyn Burns). For this twist to work, though, viewers have to ignore the fact that if this film does indeed take place in 2013, Heather would need to be 40 years old; Daddario was in her mid-20s at the time of filming, and the script writes the character and her friends as 20-somethings.
Learning of her lineage, Heather assists cousin Leatherface in murdering Burt Hartman, and they both retire to Verna's mansion as the last Sawyers left alive.
