In Dollhouse, Echo is an "Active," a member of a highly illegal and underground group of individuals who have had their personalities wiped clean so they can be imprinted with any number of new personas. Hired by the wealthy, powerful and connected, the Actives don't just perform their hired roles; they wholly become - with mind, personality and physiology - whomever the client wants or needs them to be. Whether imprinted to be a lover, an assassin, a corporate negotiator or a best friend, the Actives know no other life than the specific engagements they are in at that time.