When Universal Pictures and Focus Features picked up the rights to E.L. James' scintillating novel Fifty Shades of Grey, and its subsequent sequels, in 2013, many prognosticators and analysts thought the studios had landed a surefire hit, given the enormous popularity of the books. They were not wrong, with the adaptation taking in over $569 million worldwide from just a $40 million budget. Even if you haven't read the books or seen this movie, you likely know that this erotic story centers on Christian Grey (Jamie Dornan) and Anastasia Steele (Dakota Johnson), but this adaptation is chocked full of stellar supporting performances as well, including Eloise Mumford as Ana's roommate Kate. It's Kate, in fact, who essentially sets up her roommate's first meeting with Christian, which leads into their unique "relationship." I recently had the chance to speak with Eloise Mumford over the phone about Fifty Shades of Grey, which is available on Blu-ray and DVD starting today, May 8. Take a look at our conversation below.

I just wanted to say first that I saw Drones a few years back, and I really enjoyed it. I thought it was a really mind-blowing movie.

RELATED: Emilia Clarke Had a Good Reason for Saying No Way to Fifty Shades of Grey

Eloise Mumford: Oh, cool. I'm so glad. Thank you. That's really cool.

For awhile there, the casting of Fifty Shades of Grey was all that anyone could talk about. Can you talk about how extensive and/or secretive the process was before you found out you were playing Kate?

Eloise Mumford: Yeah, it was very extensive. You're right, it was a huge process. What's so cool about having such a massive book property is that everybody was really concerned with getting the characters exactly right in the casting. It was a pretty long process, but also really exciting. It made it that much more great when I found out I got it.

I haven't read the books, but I've heard that Kate is much more disapproving of Christian than she is in the movie. There's a scene where you can see she suspects there's something shady going on, but was there more that you shot, that didn't make it into the film, that shows that?

Eloise Mumford: Yeah, I mean, some of the scenes where she's talking to Ana about him were a bit longer, and maybe on the DVD you'll see the extended versions of those. You get that also in the second film, a lot more, when she finds out a little bit more about the details of their relationship, but she's an incredibly protective friend, and she's very concerned about Ana's happiness. So, I think you see that she's simultaneously really happy about her new relationship with Elliot (Luke Grimes), but at the same time, she's still really worried about Ana. She wants to know that Ana is being taken care of.

You can see the disparity of wealth between Kate and Ana, since Ana has this little Bug and Kate drives a very nice BMW. I read that Kate's father owns a media conglomerate, so I was wondering if that was also touched on more in the movie, that didn't make the cut?

Eloise Mumford: Just like any sort of friendship, it doesn't come into play that much. Obviously in any book you're going to have more background information because the form... there are just more pages to a book than there are to a script, and you're able to flesh out the back story of characters more, in a more specific way. But I think you get enough in the film, with the way Kate dresses and the way she carries herself, that she comes from money, but I've had a lot of friendships where there's been a difference in backgrounds between me and my friends, and any good friendship, it doesn't really matter. You care about each other as people and you care about each other as humans. That part doesn't really come into it, so that's why I think you don't see it very much in the film, because it doesn't matter to Kate and it doesn't matter to Ana. They're both just good friends.

The parts of the movie where we are outside, it had a really striking look. Can you talk about shooting in Vancouver and why you thought it was important to shoot there?

Eloise Mumford: Yeah, the movie takes place in both Portland and Seattle, and I'm from Washington, Olympia, which is like smack-dab between the two of those places, so that was really important in the film, to have the setting exactly right, because that part of the world, the Pacific Northwest, is incredibly beautiful and it's also incredibly unique. It doesn't look like the rest of the country. The weather plays a big part in that, rain is a big part of the story because it rains so much up there and it mirrors the characters' emotions so much. We shot up in Vancouver, which was a really wonderful experience, because it's so incredibly beautiful up there and it also looks a lot like the Pacific Northwest. And we were really lucky to have Seamus McGarvey, who is an incredible cinematographer. He did Anna Karenina, he's just one of the best cinematographers of our age. He did a really phenomenal job. And also, (director) Sam Taylor-Johnson comes from the world of photography, and you can really see that when you watch the film, because the tableau's of the locations and settings are so beautiful, that you can really see her experience in that world coming through. It's very specific to the book. There's a lot of description of where they are, and I think that was really important when shooting the film.

I haven't seen it yet, but I know the Blu-ray and DVD has an alternate ending. From what I read, it sounds like the ending that was used in the film was very close to the book, so I was curious if you can shed any light on how different this alternate ending really is?

Eloise Mumford: Well, I think that's the cool thing about this DVD. People are going to be really shocked when they see it, and really excited when they see it, so I don't want to give anything away. I think it's a really cool extra to have on the DVD, and I'm excited to see what people think about it.

So it really is that different then? No one will see it coming?

Eloise Mumford: I think people should just... I don't really want to say any more, because I don't want to give anything away (Laughs).

Fair enough. So E.L. James' husband is coming on to write the script for the sequel Fifty Shades Darker, which is set for 2017. Have they told you anything about what to expect from the sequel, and what do you expect to see from Kate?

Eloise Mumford: Well, I've read the second book, I know what happens and I think Kate has a really cool journey in the second book. She finds out more specifically what... she finds the contract, so she finds out more specifically what's going on between Ana and Christian. Also, she falls deeper in love with Elliot, which is cool. Yeah, I think we're all excited to get back to the grind of shooting it. It was such a fun process doing it before, going to set every day and hang out with everybody, and work on something we all care so much about. We're all looking forward to it.

I know he didn't have a huge role in the first book, but Kate does have a brother that appears in the first book, and from what I understand, he has a fairly larger role in the second and third books. Is there anyone that you kind of envision playing Kate's brother, or who you would like to see come aboard for this?

Eloise Mumford: Oh my gosh, I don't know. It's so funny because I put a picture of my little brother on Instagram once, and fans were like 'He's so much like Kate's brother!' So, now, of course, I can only think of my little brother, but he's not an actor, so there's no way he'll be doing the movie (Laughs).

I also see you're doing a movie called The Night Is Young, and I actually know (writers-directors) Matt Jones and Dave Hill.

Eloise Mumford: Oh, cool!

I hang out at iO West a lot and I see them there from time to time, but I didn't know they directed a movie together. Is there anything you can say about that role, and what it was like to work with those guys?

Eloise Mumford: Yeah, they're the best. It was so fun working on that film. It's a comedy, which I haven't really gotten the opportunity to do much before, so I was really, really thrilled to work on something that's just a straight-up comedy. It's sort of like a co-ed Swingers. It all takes place over one night in L.A. So yeah, they wrote it and directed it, and another woman, Kelen Coleman, and I, are the two women in it. It was a blast. We laughed a lot on set. It was great. I'm really excited for people to see it because it's always fun to do something that opens up new doors, and I've always wanted to do more comedy. It's a real passion of mine. Hollywood is funny, because once you start doing very serious dramas, that's all they see, so I'm excited to have a comedy under my belt and have people see that and hopefully start doing more.

Obviously the movie did incredibly well, but for those who didn't give it a chance in theaters or who might be on the fence, what would you like to say to convince them to pick it up on Blu-ray and DVD?

Eloise Mumford: Well, I think this is a great movie to watch in the comfort of your own home. I think a lot of people who are going to take advantage of that. There are those who are too shy or too embarrassed or not motivated enough (Laughs) to see it in theaters. Sometimes I miss movies in theaters, and it isn't for lack of anything except I got busy or whatever. What's so cool about this movie is it's become a cultural phenomenon, and there are so many references to Fifty Shades of Grey throughout our culture, that I think people should see the movie just so they finally understand those references (Laughs), because they are not going away. I think they'll be really pleasantly surprised with the film, even if you haven't read the books, it stands alone as a really cool, interesting love story. I'm excited for people to see it.

That's my time. Thanks so much, Eloise. It was a real pleasure.

Eloise Mumford: Thanks so much. It was so good talking to you.

You can watch Eloise Mumford as Kate in Fifty Shades of Grey, which is available on Blu-ray and DVD starting today, May 8. The actress will also reprise her role as Kate in the sequel Fifty Shades Darker, which is set for release on February 10, 2017. The final installment of E.L. James' trilogy adaptations, Fifty Shades Freed, debuts on February 9, 2018.