As the title suggests, this episode focuses on the Dollhouse's frequently referenced Attic, after Echo, Priya and Anthony were all placed there at the end of "Stop-Loss".
Topher notes that parts of Paul's brain are dead, so the only option left to him is to install the Active architecture, and even that is not guaranteed to work.
Adelle tells Topher to do it, and if they fail to revive Ballard's personality, he will make a good Victor.
Topher tells him people who are there, are kept in a fear induced state, and either they live like that forever or die.
In the Attic, Echo relives her nightmare, but eventually learns that it isn't real and walks away as Anthony and Priya are killed.
Echo starts to relive moments she has had inside the Dollhouse, and as a result realizes DeWitt has put her in the Attic.
DeWitt tells Topher that he should not be keeping secrets from Rossum, citing his role in Nolan's murder.
The man Echo is talking to tells her he was reporting weaknesses in the Rossum Corporation's mainframe.
Echo says they have to go, but finds that the man's legs have been chopped off and are being served to him as cuisine - making his statement "I have to enjoy myself" literal.
Adelle talks to Boyd about his recent performances and tells him he was responsible for putting Echo in the Attic.
For Dominic and Echo to get out of the man's mind they must perform his worst fear, which involves cannibalism.
However Arcane jumps back into his own mind, bringing Echo, Dominic, Anthony, and Priya with him.
He shows the group his nightmare, which he calls "the shape of things to come" — the post-apocalyptic world of "Epitaph One".
In the Dollhouse, Topher tells Boyd they are taking away a part of Ballard's mind so that they can use that section of the brain for other functions.
His mission is to take down the mainframe, explaining that they live in a fear-induced state, reliving their worst fears over and over.
Clyde has been killing people to free them, take away Rossum's CPUs, and prevent the nightmarish future he predicts from coming true.
Clyde asks what year is it, and Echo tells him it is 2010, which makes him believe Rossum is still a long way from completing its mission.
In DeWitt's office, Echo, along with Priya, Anthony, Topher, Ivy, Ballard, and Boyd have all joined together to overthrow Rossum.
Rachel Reitsleff from iF Magazine said "The Attic" was "a terrific episode in terms of content, momentum, surprises and emotion.
"[1] Eric Goldman from IGN said the episode, "was a really strong hour of television, delivering a lot of trippy situations and plenty of forward plot momentum as we hurtle towards the end of the series."
He goes onto say "overall, this episode was terrifically entertaining, delivering atmosphere and tension the show was lacking for much of its run.