Dollhouse is a great example of a show that got too clever for its own good. This explains its cancellation after two seasons and only 27 episodes. Though interesting and well made, even owning The Complete Second Season and watching the episodes back to back will not really help keep all the many and complex, not to say convoluted, plot elements and characters organized. This Dollhouse Blu-ray set features 13 episodes on 3 discs.
Dollhouse is a variation on the secret agent can impersonate many different people in many different guises plot. Here, people volunteer a couple of years of their life and through technology the information in their brain is erased and replaced by that of the character they have been hired to play. Once that assignment is over the information is erased and another character's profile is uploaded.
The people who are these characters are called actives or dolls and between assignments live in a compound called the doll house.
There are lots and too many secondary stories involving some master plan conspiracy theory. Some characters are or were two or three other people in past episodes or past characters have now been uploaded into new actors, and after a while you really just give up on following the bouncing ball.
After a very short while you get the feeling the only person who knows what the hell is going on and who is who is who is series creator Josh Whedon and he ain't telling.
Special features on Dollhouse The Complete Second Season Blu-ray are A Retrospective with Josh Whedon; Looking Back with Whedon and Cast; Deleted Scenes; and commentary tracks on some episodes.