James Callis with Rob Morrow

Guest star James Callis (Battlestar Galactica's Dr. Gaius Baltar) plus a straggly wig and a dash of Charles Manson adds up to a very chilling episode of CBS' Numbers, as the hit CBS drama winds down its fifth season. The British actor offered a look inside the creation of the charismatic sociopath who dared to abduct Charlie's sweetheart, Amita.

TVGuide.com: Rob Morrow had told me you were virtually unrecognizable in this role, and I have to wholeheartedly agree.
James Callis: How great is that? 

TVGuide.com: Have you ever been this hirsute?
Callis: I think I have been hairier, possibly, in a few other gigs. But half of that was mine and half was borrowed. I bet you could tell which half was which! [The producers and I] were of the same mindset that I wanted to be as disguised as possible. The wig we used for when I was in prison, we called the "Jim Morrison look." 

TVGuide.com: Did you do any research into such a cult-leader type? You brought to the role some effective mannerisms and a measured style of speech.
Callis: No, not really. That all just came with the dialogue. You know, America's obsessed with Charles Manson, and while this guy certainly isn't anything like that, you would feel uncomfortable if he sat in your living room. You'd be frightened as f—k if this guy sat down to dinner with you, because he's a time bomb. You don't know when he's going to go off. 

TVGuide.com: Was Navi Rawat (who plays Amita) prepared to go to the occasionally dark place with you?
Callis: You can see that she totally went to those places. For part of her performance, she really had to sell terror. And that is acting, because I suppose in real life I'm not nearly so terrifying. [Laughs] Part of the discussion with the director and the writer-producer was about how the worse this guy is, the meaner he is, the better everybody else looks. You want your baddie to be bad, especially in this scenario. 

TVGuide.com: Is Battlestar still calling your name? Are you recording any DVD commentaries, hitting any sci-fi conventions?
Callis: I think that on some level it will always call my name. Yeah, there are interviews and conventions and commentaries and pictures.... Although it has finished, there's a lot of life in the show. 

TVGuide.com: You and Tricia Helfer had one of the big secrets to keep, regarding that final scene [in which Baltar and Six survey Times Square].
Callis: I suppose so, though at the time I wasn't totally sure what that scene meant. A lot of people actually thought we shot it in New York. I was like, "Sadly, no."

TVGuide.com: Not at all?
Callis: It's the magic of CGI... It was a brilliant job. 

TVGuide.com: Because I work around the corner from that intersection, and I was like, "How did we miss that shoot?"
Callis: You didn't spot Tricia marching around in that dress? 

TVGuide.com: Does that cast still keep in touch?
Callis: We all keep in touch with each other, yes. Whenever you leave a message for a member of the cast, you get a message from seven back, as it's filtered out, which is cool. 

TVGuide.com: What else do you have going on right now?
Callis: I'm doing a movie right now called Reuniting the Rubins. It's a comedy-drama about a Jewish family that can't bear each other and have to come together over Passover. After that, I'm not sure what's next!

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