In an interview with EW.com Joss Whedon reveals quite a bit about Dollhouse season two.
"I'm really proud of the second half of season one,” he says, “and we're just expanding on that in a huge way: Finding out the different things that Eliza [Dushku] can be, at the same time as extending our mythology. Really, just every meeting is like, 'What's the most fun we can have with this actor?' about the whole cast. All I can say -- 'cause I'm gonna be Mr. Un-Spoiler -- is that we're having a crazy amount of fun, and usually, that tends to translate onto the screen."
He does get a bit spoilery, though, revealing that the search for Alpha won’t be picked up on straight away in season two. Alan Tudyk, who plays Alpha, has a role on ABC's V, but Whedon hopes he'll be able to use the character sparingly: "Alpha will always be a part of the equation."
Instead, says Whedon, Echo's last word in the finale, "Caroline," is the clue to her season two quest. "Echo wants to find not just Caroline, but what's going on behind everything. She doesn't have all of the skills. But she does have this weird super power of becoming a different person all the time, so she might start using that more specifically to find out who Caroline was and what happened to her and why this place exists."
With The Sarah Connor Chronicles having been cancelled, and Summer Glau back on the job market, some fans have been wondering if there might be a place for her in the Dollhouse? “We didn't honestly go into the season going, 'Now how can we figure out how to service Summer?'” says Whedon. “If something comes up that's good enough, my God, I'd hound her. But the rumours of her becoming a big part of the show are greatly exaggerated."