Surveillance drama Person of Interest had a panel at Comic-Con in San Diego, Calif., on July 20, and the show's cast and crew revealed a few details about season 3.

The biggest piece of news to come out of the Person of Interest panel was that Amy Acker, who had a recurring role in the first two seasons as Machine-obsessed cyber-hacker Root, was promoted to series regular when the show returns in the fall.

Acker was last seen as Root in the season 2 finale in a mental institution getting a phone call from The Machine. Enstars previously reported that Acker was hoping she would be back for season 3 despite not getting the call from producers yet.

"Every time I read a script I'm just like, 'I get to say that?'" Acker said at the Comic-Con panel over the weekend. "I don't think that she's mean, it's just if people don't do what she tells them to she gets upset."

Acker is the second actress to be promoted to series regular for season 3 after Sarah Shahi, whose upgrade was announced in May. Shahi plays Samantha Shaw, a government assassin-turned-ally to Reese (Jim Caviezel) and Finch (Michael Emerson).

"The thing that I love the most about her is her unpredictability and the fact that she really could go anywhere," Shahi said at the panel. "We talk about her being the female Jason Bourne and at this point she really is a man with no country."

As for other recurring characters, Person of Interest executive producer Greg Plageman announced that crisis management specialist Zoe Morgan (Paige Turco) would be coming back for season 3.

"Oh yeah, Zoe's the fixer and she needs to get fixed," Plageman explained, "so she's coming back."

It was also announced that Warner Bros. and CBS were in the process of launching the Person of Interest Social Photo Opportunity, which allows fans to submit a photo of themselves to Facebook in the hopes of seeing it on a future episode. Though the Social Photo Opportunity is still in the works, fans can learn more information at the Person of Interest Facebook page.

Person of Interest debuts in its new Tuesdays at 10 p.m. timeslot, starting on Sept. 24 on CBS. Watch this Person of Interest video that premiered at the Comic-Con panel: