'A Christmas Prince 3' Stars Credit Meghan Markle and Prince Harry for Franchise Success (Exclusive)

A Christmas Prince: The Royal Baby
Cos Aelenei/Netflix

Rose McIver and Ben Lamb dish on the most 'ludicrous' moments, a fourth film and why they're game for a new holiday (and locale).

Warning: Do not read this interview if you have not watched A Christmas Prince: The Royal Baby. There are major spoilers from the movie.

When the holidays roll around each year, the chances of a new A Christmas Prince movie waiting to be devoured on Netflix are high. We've seen the fictional royal couple of, Aldovia's Queen Amber and King Richard, blissfully fall in love and get engaged in the first movie, which dropped in 2017. We've seen them say their "I do's" in the sequel the following year in A Christmas Prince: The Royal Wedding. And now, we get to experience them becoming parents for the first time, as they await the arrival of their baby in, you guessed it, A Christmas Prince: The Royal Baby.

But of course, there has to be a holiday obstacle for the main couple to face and this film is no different. In The Royal Baby, a 600-year peace treaty between Aldovia and Penglia goes missing before Amber and Richard can sign it before the stroke of midnight on Christmas Eve, threatening a worrisome curse on their first-born (a girl, by the way). There is never a question about whether Amber and Richard will successfully kick their main source of strife to the curb -- spoiler alert, they're successful! -- but it's all the twists and turns that make this particular movie a cheesy, exciting adventure.

With the latest A Christmas Prince movie now streaming, ET caught up with Rose McIver and Ben Lamb about why they credit real-life royal couple Prince Harry and Meghan Markle for A Christmas Prince's success, the most "ludicrous" moments that everyone will be talking about and ideas for a potential fourth movie.

ET: A Christmas Prince has become a yearly tradition for a lot of people when the holidays roll around. Has this been a wild journey for both of you, three films in?

Ben Lamb: It madly coincided with the whole Harry and Meghan real-life story, didn't it? And I think with also a bit in need of some Christmas magic or at least some kind of simplicity and happiness in their lives when the first one came out. So, yeah. I mean, I'm delighted somewhat, but I don't think either of us did expect it.

Rose McIver: Yeah, I was kind of shocked because I felt like we've seen stories like this so many times. And this seemed to strike a particular chord at this particular time and kicked off this franchise that's now happened. We've got three films out of Amber's very questionable journalism. It's been such a nice ride.

I'm speaking for myself, but I love this time of year because I'm such a fan of feel-good holiday movies that make you feel all warm and fuzzy inside. Are you guys fans of holiday films? Do you tune into any this time of year?

McIver: My go-to is National Lampoon's Christmas Vacation for Christmas movies. But I actually understand this interest behind wanting to get lost in a bit of escapism. I came into weird things like this British show, Million Dollar Intern, I think it's called, which just makes me dizzy. It's kind of bizarre but a simple premise -- something that's not deeply challenging to my brain, it's not confronting. It's something that is soothing. It's a comfort space and I think people do need that, for sure. We don't always want to listen to sophisticated music. Sometimes we need this analogous frequency that can just chill you out, so I get the appeal. I mean, I don't quite understand the watching it 53 times in a row or whatever, that's dedication. 

Lamb: That transcends Christmas.

You've both played these characters, Queen Amber and King Richard, for three movies now and every holiday, there's a new one dropping on Netflix. Do they feel like another member of the family at this point? Do you miss them when you're not making these movies?

Lamb: Well, I would say that a lot of the characters in these types of movies are as close as we have these days to old school, stock characters. And so, they're not necessarily the most complex to play. I think that the exciting thing about doing this job is the fact that you get to... The challenge is to put in as much reality and empathy, in what could easily come across as two-dimensional characters. I think that's what I've tried to do, certainly, is to make them real and relatable.

McIver: Yeah, I totally agree. I think the one really surprising character for me is Simon (played by Theo Devaney), because they've turned the stock character on its head. And suddenly the villain is the good guy and then the villain again. It's quite hard to keep up and I think that's part of the roller-coaster of A Christmas Prince -- knowing who to trust. It all depends on sequential films that we're looking to reinvent. In general, we're trying to give a lofty idea just enough gravitas so that people care. I do think we tried to imbue them with enough vitality that when they get together, they survive their troubles and they make it work. Especially for the people in their living rooms at home, who have been through their own various heartbreaks. It's a really fine line because we don't want to take it too seriously, but we do need to breathe a certain amount of integrity into these people. Otherwise, who cares?

Cos Aelenei/Netflix

Let's talk about the plot of A Christmas Prince: The Royal Baby because it sounds a little out there on paper. What threw me at first was that there's a centuries-old treaty between Aldovia and Penglia that needs to be signed before the stroke of midnight on Christmas Eve, otherwise there is a curse put on the firstborn, or Amber and Richard's baby. When you were reading through the script, what plot point made you think, "This is bonkers!"?

McIver: I'm still kind of hung up on the cryptocurrency plot from the second film. (Laughs.) I still have to think about it to kind of understand what happened, but I think this might be a little bit of the journey with the treaty in this film. It's a pretty complicated story! Somebody who's bringing another person to the world is having to put a lot of time into it. I think it's a pretty bulky story for sure.

Lamb: I think the first time I read it, it seemed like it was a very supernatural plot line. But actually, what would be interesting is you can take it as being supernatural. Or you can take it as being two people who are just trying to do everything but can't for their unborn child, and are worried about doing this thing wrong.

McIver: Absolutely, I totally agree. I also think that what's magic about these films is that we do try to introduce a different source of conflict each time. It's almost the film you've seen a million times before but sometimes things are a little off and that works in our favor. I think when you think you know how this is going to unfold, you don't, and something strange always goes down. That was, for us, incorporating this mystery and it isn't exactly the genre that you would expect but again, it keeps it fresh. 

Speaking of surprising twists and turns, I was taken aback to learn that the culprit who stole the treaty was the butler, Mr. Little! I was sure it was Simon. Were there any twists? 

McIver: I was definitely surprised at how many people Richard and Amber let into delivery with them, personally. (Laughs.) 

Lamb: I think what's not surprising is quite how into the baby-naming situation that Queen Helena (played by Alice Krige) and the rest were because they're super invasive about trying to run up the gender of the baby.

McIver: Yeah, yeah, absolutely. Alice is such a master of juggling exactly what we talked about, the integrity, the feasibility of these characters with the fun of it all. And she's so committed. She did everything -- to situations that it can be quite hard to find the reality and it's revealed in a way that she does. And that's again, part of what works. As ludicrous as the situations could be, people try and find something relatable in there.

Lamb: The situations are ludicrous, so without looking at them with a relative sense of seriousness, a little bit of tears, they would be like, "Well, what's the point?"

When Simon proposed to Melissa, it seemed like that was opening the door for a potential spinoff with that particular couple. Is that something you would like to see? Simon is a duke now...

McIver: I mean, anything goes right? I would watch that. I'd watch that movie.

Lamb: There are Easter eggs popping up in all kinds of other Christmas films on Netflix, so that would kind of work.

In The Knight Before Christmas, one of the characters gifts an ornament their grandparents bought on a trip to Aldovia, so Aldovia definitely exists in the Netflix holiday movie universe. 

McIver: Oh man, bring it on! From your lips to God's ears.

Lamb: It'll be just like The Avengers. You heard it here first: Christmas Avengers!

Cos Aelene/Netflix

We've now seen Amber and Richard fall in love in the first Christmas Prince, then get married in The Royal Wedding and now having a baby in The Royal Baby. What's the next chapter in their love story? Because I'd personally like to see a fourth movie.

McIver: I've made a few jokes about this stuff, but in all seriousness, I actually think Princess Emily (played by Honor Kneafsey) is due a bit of time in the spotlight. She's such a great character and she's 14, I think, now in real life. There's totally room for her evolution and coming of age. I think there's something really interesting there. That's where I would go with the story.

Lamb: See, I'm being more pragmatic about this. I think we should do a Christmas holiday. A Christmas holiday movie where we go somewhere really nice and warm. I love filming in Romania in the snowy mountains, but I think we could definitely do a Christmas holiday in, like, Thailand. 

McIver: There you go!

Rose, you're wearing a prosthetic pregnant belly for almost the entirety of the movie. Was that specifically challenging for you?

McIver: It's a funny thing where I thought it was going to be all the fun of pregnancy and none of the hard stuff, where people would carry me around on a cushion and break for me when I walk through doors. And there was a bit of that, but there was also... I didn't realize quite how much it squashes your diaphragm. It's such a silly little thing, but Amber is pretty active in the third movie. She's not on bed rest at all. She's in an archery competition. And not being able to breathe to the bottom of my stomach, I guess it reminded me that maybe I'm a good diaphragm breather, but I wanted to sense this thing that all of the other very real physical pain that people go through being pregnant with swollen ankles and everything else. I was like, "Oh, squashed diaphragm, didn't know that was in the equation." And it was.

What I've realized too is every big life moment for Amber and Richard happens on Christmas -- and I'm well aware that's the franchise. They fell in love on Christmas, they got married on Christmas, they gave birth to their baby girl, Elleri, on Christmas. Do you guys hope that the next one isn't set around the holiday? 

McIver: Well, I think in all seriousness this has become a pitch meeting. I think about Christmas holidays in Aldovia and I think that it would be good to do it Down Under where Christmas is summery. I feel like growing up in New Zealand, it's fully portrayed as a white Christmas and we didn't know that it's not for half of the world. Christmas is barbecues and beaches and long summer nights. I think they are well overdue for a bit of a sunny Christmas getaway and it would be a good opportunity for me to exploit all of my resources in New Zealand.

Lamb: Or we can just do all the holidays. I feel like we can see The Easter Prince. I can see The Halloween Prince. We can make five or six of these a year. 

McIver: What about a Bastille Day Prince? (Laughs.)

Lamb: Oh perfect, yeah yeah yeah. There's no limit!

A Christmas Prince: The Royal Baby is streaming now on Netflix.

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