Echo (Eliza Dushku) is an Active and star of the series. She is one of the most popular Actives in the Dollhouse, and, during the course of her engagements, has shown skills that transcend the limitations of her parameters. Echo has become increasingly self-aware during her blank state. Prior to having her mind wiped, Echo was a college activist named Caroline Farrell.

Boyd Langton (Harry J. Lennix), a former cop, a handler at the Dollhouse assigned to Echo until he becomes the new head of security. He has doubts about the ethics of what the Dollhouse does with the Actives. It is clear that he cares for Echo, and will go to any lengths to protect her.

Topher Brink (Fran Kranz) is the scientist who operates the Dollhouse technology and uses it to imprint new personalities on the Actives. He has stated that the technology takes imprints from existing people, which he then mixes and matches to create the desired imprint.

Paul Ballard (Tahmoh Penikett) is the ex-FBI special agent assigned to the Dollhouse case. While most in the Bureau view the case as a joke, he takes it seriously, to the point of obsession. Throughout the show, his main objective is to rescue Caroline. He had become involved with his neighbor Mellie before discovering the Dollhouse imprinted her to spy on him. In "Omega" he agrees to help the Dollhouse find Alpha.

Victor (Enver Gjokaj) is an Active who has made friends with Echo and Sierra. The character is introduced as Russian gangster Lubov, whose real identity as a Doll is revealed later. The character is also regularly hired out on romantic engagements for one "Miss Lonelyhearts." In his mind-wiped state, he is inexplicably attracted, physically and emotionally, to Sierra. He suffers facial cuts similar to Dr. Saunders after a run-in with Alpha.

Sierra (Dichen Lachman) is the most recent Active to be added to the Dollhouse. Prior to having her mind wiped, her name was Priya. She is instinctively drawn to Echo, but lacks her self-awareness. She was raped by her handler Hearn while in a blank state. Topher has done his best to rid her of these memories, but subsequent episodes reveal that he was not entirely successful.

Adelle DeWitt (Olivia Williams) is the highest ranking official at the Los Angeles Dollhouse. She truly believes that what they do at the Dollhouse helps people. Although Adelle is the head of her Dollhouse, she does answer to off-screen superiors, as the LA Dollhouse is just one of more than twenty worldwide. She is revealed to be "Miss Lonelyhearts" who has hired out Victor several times.

Whiskey (Amy Acker) is originally introduced to the series as Dr. Claire Saunders, who serves as the Actives' general physician. It is revealed in "Omega" that she is an Active. Formerly the Dollhouse's most popular Doll, she was attacked by Alpha with a pair of scissors, causing extensive facial scars. When Alpha killed the actual Dr. Saunders shortly afterwards, Whiskey was imprinted with his personality and skill-set.

November (Miracle Laurie) is originally introduced to the series as Mellie, the neighbor, romantic interest, and confidante of Paul Ballard, but Mellie is in fact a "sleeper" Active. Adelle can switch November to a combat-ready personality using verbal codes. In "Omega", November's original persona and memories are restored and she is released from her contract early with full payment at the request of Paul Ballard, in exchange for him joining the Dollhouse's staff; she returns to her life as Madeline Costley, in which she had a deceased daughter named Katie.

Alpha (Alan Tudyk) is a rogue Active who escaped the Dollhouse. An accident causes a "composite event", in which 48 personalities are simultaneously imprinted on Alpha, along with the associated memories and skill sets. In his escape, he killed several Dolls and Dollhouse staff members, including Echo's previous handler, yet he let Echo live. After his escape from the Dollhouse, Alpha begins to send anonymous packages to Paul Ballard, hinting at the existence of the Dollhouse and at Echo's former identity. Alpha reveals himself after posing as former Los Angeles Dollhouse architect Stephen Kepler, whom Ballard has tracked down. He leads Ballard into the Dollhouse, takes control of the security and automated systems, and leaves with Echo. Though Echo escapes him, he remains at large.

Ivy (Liza Lapira) is Topher's assistant. While she is highly skilled and sees herself as his apprentice, Topher treats her more as a gofer, assigning her menial tasks such as fetching him snacks.

Laurence Dominic (Reed Diamond), head of security at the Dollhouse during most of the first season, takes his job very seriously, but doesn't think very highly of the Dolls themselves, viewing them more as pets than humans. He attempts to kill Echo, and also suggests she be retired as an Active, and put into "the Attic". Later, while intoxicated, he attempts to apologize to Echo for his actions. Dominic is revealed to be an NSA agent who is monitoring but not exposing the Dollhouse for unknown NSA purposes. Upon discovery, DeWitt has Topher extract his persona from his body and then sends him to the Attic.

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