Smith chatted about his future as the Eleventh Doctor, the timing and manner of Amy and Rory's departure and what he would like to do next. Plus, find out what the cast's nickname is for "Doctor Who" showrunner Steven Moffat.
Karen, do you have anything on a bucket list for Amy? Is there anything you want her to do before she leaves the TARDIS?
Gillan: I don't know. I kind of, I know how I want her to go, and I actually know how she goes now ...
Really? Can you tell me?
Gillan: No I can't! Absolutely not! But I know that I want her to go out in all her sort of glory.
I was just watching a clip of "The Girl Who Waited," where you've got that whole "Kill Bill" look going on, with your sword, I just thought it was fantastic. Is that the kind of ass-kicking way you want to go out?
Gillan: Yeah! [Laughs.]
During a panel session Q&A with the capacity crowd, "Doctor Who" executive producer Caroline Skinner confirmed that the Weeping Angels will be involved in Amy and Rory's departure in a dramatic Season 7 Episode 5, written by Moffat.
The cast had their first read-through on March 23 and the episode will be shot in New York City.
And how about you, Matt, are you staying on?
Are you staying on after next year?
Smith: Well, I mean look, we've got the [50th] anniversary coming up, there's another Christmas special to shoot, we've got another season with our new companion coming in, there's a lot to be getting on with before I leave. So absolutely, I'm here for the foreseeable future.
Lots of fans are going to be overjoyed to hear that!
Smith: I hope so.
Are there any villains or characters you want to re-encounter?
Smith: Do you know what? I always really liked Prisoner Zero from 'The Eleventh Hour' ...
Gillan: Oh yes, that would be fun!
Smith: Yeah, that would be fun to have him come back some time, wouldn't it?
Gillan: Yes, and that was your first monster."
Smith: [Laughs.] Not on set though, you were my first monster!
You've both recently played very iconic British characters not related to "Doctor Who" -- Christopher Isherwood and Jean Shrimpton. Have you got any other real-life people you think you'd like to be playing soon?Gillan: Oh, that's a really difficult question ...
You've got completely the right profile to play Chet Baker.
Smith: I hope so.
Gillan: I love that poem by Ted Hughes. I can't remember what it's called, but at the end it's like, "They wore each other's faces." It's about a married couple snogging each other for the first time.
Smith: He's amazing. I'd love to play him.
How about you, Karen?
Gillan: I have no idea. I'd like to play some sort of singer. That would be really cool. But I keep on doing things from the '60s, but that's because I really like the era.
Smith: You have got a bit of a '60s thing going down.
Gillan: Yeah, I just really like it. So what I'd like ideally is to play someone from that era, but maybe I should branch out from that. [Laughs.]
Like head to "Corsetville" or something?
Gillan: For a while, yes!
Would you ever be tempted to do episodic American TV? You know, like a 23-episode series?
Smith: Of course, they have great television out there like "True Blood."
David Morrissey's joining that next season.
Smith: No way!
Yes, he's signed up for Season 3 playing the Governor.
Smith: Oh I love David Morrissey! He's brilliant. And there are loads of actors doing really well out there. We're both quite intrigued by the States, aren't we?
Gillan: Yeah. I mean, I honestly just want to do good projects and they have amazing projects over there, so if the right one came along then I would totally do it.
Because "Doctor Who" specifically is such a cultural institution here, do you worry that by committing yourself to "Doctor Who" right at the beginning of your careers that it's possibly going to be a millstone further down the road? Or do you think it's just the best opportunity?
Gillan: I think it's the best opportunity. I don't worry about that. At all. I don't see the point in worrying about that, and also, it's not something I would ever want to be disassociated with, so I think it's just an amazing thing and I would gladly be connected to it for the rest of my career.
So you'll be coming back for the 25th reunion then?
Smith: I have exactly the same answer. I mean, it's such a privilege to be part of the heritage of the show. And the opportunity to be a part of the changing stories every week, to travel the world, to develop some of the closest relationships I've had in a working environment, with Karen and Arthur [Darvill] and Alex Kingston. [Gillan laughs.] Don't laugh! It's true!
You have got such a brilliant cast, though, and the writers are so good.
Smith: Yes, and we have a right laugh. Steven's a hero.
I do find it amazing that the American audience has just welcomed it so wholeheartedly over the last two seasons. For them, it's not part of their cultural frame of reference. I've been talking to some women who've come over from the States just for the weekend ...
Smith: No way! That's so exciting!
Yes, and they were saying how they watched it as teenagers on PBS and now they can go to a coffee shop and they hear people talking about it, and that just never happened before.
Smith: That's amazing. I'm not sure if you're aware, but last year in the States "Doctor Who" was the most downloaded show of the year. That was astonishing.
I think many viewers in the States are crying out for decent, well-written and well-acted dramas because in recent years, they've been inundated with reality shows.
Smith: Even with all the good stuff they've got out there, like "True Blood" and "Mad Men?'"... Though "Mad Men" doesn't have a huge audience.
I mean, BBC America's making huge inroads ...
Smith: It's true, and they've really supported us as well, so we're very grateful to everyone at BBC America. And hopefully, the plan is to continue to just get bigger and bigger out there. You know, we're going to Comic-Con this year, which will be great.
Gillan: And also, there is a "Doctor Who" bar in New York. A themed bar with Gallifreyan cocktails!
[Laughs.] Is that so?
Smith: So we randomly just walked into this bar ...
Gillan: A local told us about it, so we had to go see it.
Where is it?
Really? I lived in New York for 10 years. It must have turned up after I left.
Gillan: What was it called? The Way Station or something?
Smith: Hang on, I've just got to show you the toilet. Or, the outside of the toilet. [He picks up his phone and starts scrolling through his pictures.] You will not believe ... that's the toilet! [He shows a photo of him and Karen standing in front of the toilet door, which is painted to look like the door of the TARDIS.]"
Oh my god. You know, everyone drinking in there must have thought they were hallucinating.
Smith: All of the drinks are like "The Eighth Doctor" and "The Rose Tyler" and stuff.
So, I was wondering ..."Doctor Who" has got such amazing special effects. How much do you think that's affected the success of the show? We've left the wobbly sets behind, and the show now has such a cinematic quality.
Smith: It is, of course, but it's also the tone. It's the color of the show and the tone of the show and the style and the cameras on which it's shot that have made it cinematic as well. But I think the development in effects have definitely transported the show in a really brilliant way. But I think at the heart of it, you know, if you look back, you have episodes like "Genesis Of The Daleks." With or without effects, that's a great episode.
Yes, it's the plot and the script, isn't it?
Smith: Yes, and like "Tomb Of The Cybermen," because at the heart of it, you have a man who shouldn't really be able to solve and get out of the problems that he's in, but he can do it -- hopefully with wit, brilliance and silliness -- and that is the essence of the show. Hopefully, with a hot chick behind him! [Both laugh.]"
Gillan: I agree. That's what I enjoy watching about it as well.
Do you think sometimes the effects can get in the way?
Gillan: I don't think they get in the way, and if they're really good, I find it like a really great bonus.
Smith: And we love an explosion and the CG stuff that they do. Like when you look at, for instance, I don't know, there are so many great things ...
Gillan: Things exploding in the sky. That's always great!
Smith: Like in "The Big Bang," Season 5, Episode 13.
You've done your homework! Do you sit at home learning them at night?
Smith: We decided for some reason to ... go on, do one!
Gillan: Oh, okay. 'The Lodger.' Season 5, ah no, what episode was that? Episode 12!
Smith: Episode 11.
Oh, close. Nearly!
Smith: We find it fun to name all three things, like "The Hungry Earth," Season 5, Episode 8 ...
You'll find some fans who'll test you on that.
Smith: Yes, they know more than us. But we've got "The Moff." He knows all the stuff.
Yes, he's got it all sealed-up in there.
Smith: Did you know that people have started to call him "The Moff"?
Like "The Hoff?"
Smith: Yeah, well he is like The Hoff, but smaller and more intelligent. No disrespect to The Hoff -- I'm sure he's very bright -- but Steven is a bona fide genius.
So one last question: This week, a lot of people have talked about the fact that Steven's hired a new young, cute girl to be your next companion. And he's taken quite a lot of flak in the press with people saying, "No, it should be an older woman, or it should be a man."
Smith: The thing is, if it was an older woman or a man, an older woman say, for instance, they'd say it should be a cute girl. And if it was a man, they'd say it shouldn't be a man, it has to be a woman. Basically, and this is one of the great virtues of the show, is that it divides opinion. But there are some, in some quarters who, whatever we do, they'll fall on the other side of it and go, "You're wrong, it should be like this." There has to be a voice for that ...
Gillan: I just think there's no right answer.
Smith: And I think you've got to trust one of the most successful writers in current British television. "Sherlock" and "Doctor Who" are undoubtedly two of the best shows on television at the moment. Also, we didn't just stumble across this girl. It was a very thorough process.
Gillan: And also, it's not like the companions are written, "Oh, young cute girl." It's just the character and then they find the best actress for that role.
Smith: Yes, it could have been any age, but we landed upon, you know ... "
She looks like she's going to be good, I think. She's feisty, and I think it will be an interesting dynamic.
Smith: It's exciting, but of course it's very sad to lose Karen and Arthur because, as I've said, they're great friends and I think they've been just the best companions.
Oh, it's been fantastic. And one last question. One specific question. Do you think they could ever have an American actor playing Doctor Who?
Smith: Who knows? Never say never. There's talk of a "Doctor Who" film where they're going to get in a different doctor and all that sort of stuff.
That's Helen Mirren, isn't it? She says she wants to do it.
Smith: [Laughs.] Helen: If you're listening, I know you don't want to be a companion, but come on! Come and do an episode with me, and then be the doctor!
"Doctor Who" Season 7 premieres fall 2012 on BBC America.
New to "Who?" Check out HuffPost TV's guide to the five essential episodes.
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