Sigourney Weaver is no stranger to monster movies. In 1979, she broke onto the scene and became instantly iconic as the extraterrestrial-besting Ripley of Ridley Scott's Alien. While that franchise has moved on without her--most recently to the upcoming Alien: Covenant--Weaver is bringing her powerful onscreen presence to a different kind of creature feature with A Monster Calls.

Based on the adored YA novel by Patrick Ness, A Monster Calls is a poignant drama that focuses on a young boy (Lewis MacDougall) who copes with his invalid mother's fast-approaching death by befriending a towering, tale-telling yew tree (Liam Neeson). Weaver co-stars as the boy's concerned but stern grandma. It's the first grandmother the 67-year-old actress has ever played, and a role into which Weaver resolutely sinks her teeth.

When Screen Rant spoke with Weaver, we not only got into A Monster Calls and its layered approach to character development and exploring grief, but also what the world-renowned actress makes of Alien: Covenant, the role of women in sci-fi, and why heroines have been so central to the Alien franchise.

So this is the first time we've ever seen you play a grandma, but she's a different kind of grandma. Can you tell us a little bit about her?

Sigourney Weaver: Yes, she's an old-style grandma, in that she has a lot of rules and she is very strict and not very empathetic in the beginning. She doesn't have a very good relationship with her grandson. One of the reasons I wanted to be part of it, very rarely do you have a chance to play someone like that who then becomes, goes on a journey and transforms. You see what's underneath all that armor. Often times, especially playing an older character, you would just see the unsympathetic part but this movie takes care of all of its people and you get to know all of them during the course of it.

Sigourney Weaver as Grandma in A Monster Calls

It really deals with how people react to grief in various. I was especially drawn to the fact that on top of that it talks about validating children's fear, because I think a lot of people want to sanitize kids films and not make them too scary. When I was a kid that was the stuff I was really drawn to because it acknowledged things that I felt. Was it important to you to be involved with something that dealt with children in this kind of way?

Sigourney Weaver: I think it was very important to me because I worked for a number of years with Maurice Sendak to start a children's national theater and Maurice was always writing very dark things because he said, "Children think about all this stuff and it's a big part of their world." We make a big mistake if we, as you say, sanitize it. They can tell that's not real and also, I think when you protect them they get more afraid because then they go, "What's happening?" There are monsters. So I think in the course of this movie you see the power of the imagination and how this little boy really needs to really come to terms with the complexity of this experience for himself.

And also the complexity of the people around him, which was another thing regarding your character, where I could relate to her sense of, "How I'm going to deal with a bad situation is to plan ahead." And I thought it was really interesting the way they work within those realms to setup these things. What about the script particularly attracted you?

Sigourney Weaver: What I found really moving was, for the grandmother especially, if you will just do, everything I tell you to do, it will save you. That's the kind of way you try to think, try to control a situation. I thought it really, the film and the script and Bayona himself, really approached the movie with the idea of telling the truth and not giving any easy answers and respecting the whole spectrum of experience for all these human beings. I felt it was a very rich film that a family could watch together and it would be a very powerful experience to watch with your family, especially if they were going through anything like this.

I think I can totally relate to that. We'll see this Christmas. I wanted to ask you, with Alien: Covenant coming out, we have another film in the franchise that deals with the female heroine. As someone who grew up watching Ripley, I'm curious is you have any insight as to why female heroines have been so central to that world?

Sigourney Weaver: I don't know. Actually, I think that's not true...you mean the Alien world? Because in general it's great that they're having now, like in Rogue One with Felicity, so many female heroines - it's about time. I think that Ridley has always wanted to make another Alien movie, perhaps it has a woman with a central role. I don't much about it. I know Katherine Waterston, she's worked at our theater. She's very talented.

I got to talk to her about it a little bit yesterday. She's very quiet. But it seems very clearly there's a continued line.

NEXT: Liam Neeson & Lewis MacDougall Interview For A Monster Calls

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