In the year 2020, Echo and her surviving Dollhouse crew attempt to restore order to a devastating future world before mankind is eliminated.
Sacrifices are made when Echo leads her crew to Arizona to dismantle the Rossum Corporation's mainframe.
Topher races to reconstruct Echo's original personality and memories when Adelle realizes they are the key to averting a devastating future. Meanwhile, Echo and Bennett's shared past and the identity of The Rossum Corporation's mysterious leader are revealed.
When Adelle, Boyd, and the rest of the Dollhouse fear that Echo's uncontrollable mind imprints are making her a danger to their goals, they send her to "the Attic" where Echo is forced to face her worst nightmare in order to survive.
As his contract with the Dollhouse expires, Victor is released back into the world, where his military past threatens his future with Sierra. Meanwhile, Echo is deemed too dangerous and is sent into her worst nightmare.
Echo and Bennett have a shocking meeting as Adelle goes head-to-head with the ruthless head of the DC Dollhouse. Topher sees double when he must involve Victor in his espionage. Perrin finds a surprising witness to testify against the Rossum Corporation, but find he may be living in a house of cards.
When Senator Perrin makes his stand against the Rossum Corporation, Echo attempts to stop his expose. Adelle, and Topher begin to see what they are up against in the rival of Washington DC.
Sierra is forced to face her past as her connection to the Rossum Corporation leads to obsession and murder.
Echo is a member of a highly illegal and underground group of individuals whose personalities have been wiped clean so they can be imprinted with any number of new personas. Confined between missions to a secret facility known as the Dollhouse, the "Actives" are hired by the wealthy, powerful and connected to wholly become—with mind, personality and physiology—whomever the client wants or needs them to be. They know no other life than the specific engagements they are in at that time—or do they?