If you only know Doctor Who," last year's under-appreciated indie western "In a Valley of Violence," and "The Circle" (also currently in theaters), is charming, excitable, and very sweet, all of which makes her transformation into the revenge-seeking Nebula even more impressive.

In "Guardians of the Galaxy Vol. 2," Gillan really gets to play with the character, delving deep into her back story, getting far juicier scenes with her adoptive sister, Gamora (Zoe Saldana), and the rest of the Guardians, and allowing the character to have more dimension and complexity. It's a lot of fun.

So it was a thrill to get to talk to Gillan about the character, the progress of Nebula, whether or not she's a part of the upcoming Disneyland ride, and what she thinks of a female Doctor Who.

Moviefone: You're back! Was it a surprise that you were coming back?

Karen Gillan: I knew I was going to come back but I didn't know in what capacity. So it was really cool reading that script for the first time and feeling like the character was evolving so much and you were learning so much more about her backstory and her relationship with Gamora was being explored in-depth. I was over the moon.

Some of the scenes between you and Gamora felt like they should have been in the first movie. Was it exciting to finally get to play that?

It was so exciting, and there actually was a scene like that in the first movie but it ended up getting cut, where we hinted at what went on with them. It was never explored as in-depth as what we do in the second movie. And I think it was actually smart to save it for the next movie, because it adds to the layers and held some things back before giving it back to the audience. It was amazing. I was so excited about it. It's so interesting.

When I was auditioning for the character of Nebula, this is what I found the most interesting and what attracted me to the role, the relationship between these two women and the abuse that they suffered. That was something that I thought, I can grab onto that. I can run with that. I was so excited that I got to!

Did you talk to James in-between and say, "I'd really love to do this with Nebula."

No, I never did, mostly because James is a genius, and I don't think he really needs my input. But I think he knew that. We had talked about the character before I did the screen test and we had talked about this relationship. In the screen test, the scene I performed was very much geared towards that vibe, instead of a villain-y vibe. In fact, it wasn't villain-y at all and I had to make it more villain-y for the first movie. But that was something that we discovered in the screen test. It's so cool, because in the second movie we're finally getting back there. And he said, "I finally saw what I saw in you during that screen test." It was like: yay!

The first film was a pretty unknown quantity. When did you feel like you guys were making something that was really going to connect with people?

I always had a lot of faith in it because it's Marvel and they had such a success rate, it's ridiculous. But "Guardians" was the risk. Nobody really knew what it was; it was this random comic. I definitely had a great time filming it but, again, you just don't know. However, when we first screened a trailer at San Diego Comic Con for the first movie, and there was this long pause, or at least what felt like a long pause, afterwards, and it was like, Huh, I've never seen anything like this before. That's when I got really excited. Because it was like, We're onto something special, because it's new. That's so important.

You have a really great arc in this movie, in that you get to be a villain, a Ravager, and a Guardian. What aspect was the most fun to play?

I'm going to go with villain. Villain is pretty fun. And if she's going to be a Guardian, she'll be a reluctant one. Or at least pretend to be. I think she does want to be accepted into the family but she'll pretend that she doesn't care.

She's like the teen that huffs and goes back to her room.

Yeah, she's a little emo.

Last time I saw you, you were on set, and you'd said you'd gotten the make-up down to a more manageable situation.

So, on the first movie I had to shave my whole head, which was a really cool experience and liberating. But at a certain point, I was being called "sir" too much because I'm also really tall so from the back I just looked like a boy. But on the second movie, they'd told me they'd figured out a way where I just had to shave part of my head. So I just had to shave the under section. And that was great.

You have long hair now and you're shooting "Avengers: Infinity War." So is it all just under a cap?

Yeah, they keep gifting me more hair each movie. Some people get raises, I just get more hair. They're just working with it.

Did it cut down on time, in terms of you applying everything?

Well, me and Zoe take about the same time, which is four hours total. But on the first movie it was five and that was without the hair. So the actual application of the make-up is 2 and a half hours, then there's an hour with the bald cap and then getting dressed. So it adds up.

You're about to enter the big Marvel universe with "Avengers: Infinity War." Are you excited about that?

So excited! We started that in January and it's been incredible.

Are you in the Disneyland ride?

No, I'm not! But I'm going to go on it and take photos and put my picture on the posters.

What is your favorite piece of Nebula merchandise?

Being a LEGO is pretty cool. Having a LEGO version of yourself is pretty cool.

Do you have all that stuff?

Well, there are a few dolls of myself from "Doctor Who," as well. But I didn't own any of them. Not having them is maybe just as weird. So I am going to start collecting them.

It would be cool to have a closet full of your toys and then maybe send people in there when they ask where the bathroom is.

I'll be like, "Oh, my mistake. It's actually to the right."

You've been a part of two pretty big franchises, with "Doctor Who" and "Guardians of the Galaxy" and you're about to be in "Jumanji: Welcome to the Jungle." Is there any trepidation on your part signing up for these things that could last years?

Not really. I think that there's actually way bigger commitments that other actors make, like TV shows that last seven years, so it's not really such a huge commitment in the grand scale of things. And, also, it's sort of a no-brainer, I like Marvel and I loved the original "Jumanji" so much. It was things that I just couldn't say no to. So it's like, "Yeah, I'll do it."

Do you still watch "Doctor Who"?

I haven't caught up on the more recent stuff, but I really need to because I want to see Pearl.

Do you want a female Doctor Who?

YES! I think we should have one. Anyone who questions whether or not a female can play that role is insane because of course she can. Because of course she can. There's a ton of actresses who can play that role, and it would be really cool. We do need a male in the TARDIS because we have a female companion.

Well, there could be a male companion?

Yes, so we should have a female doctor and a male companion. That would be good.

Earlier this week, James announced that he's coming back to write and direct "Guardians of the Galaxy Vol. 3." Are you excited?

I'm so excited! Because, you know, these movies are so him. They're his sense of humor, his taste in music. The essence of him is all over these movies. So it feels like these movies are in the safest hands possible when it's him.

"Guardians of the Galaxy Vol. 2" is out this week, everywhere in the universe.