Although Melissa de la Cruz’s husband, Michael Johnston, has been collaborating on all of her YA novels since the first book in the Blue Bloods series, his name has never appeared on the jackets along with his wife’s – until now. Johnston, an architect and writer, is billed as co-author on Frozen (Putnam, Sept.), the first in the couple’s post-apocalyptic Heart of Dread trilogy, in which Earth has frozen over and the only remnant of civilization is a city called New Vegas; Natasha, a 16-year-old blackjack dealer, encounters many dangerous obstacles in her effort to reach “the Blue,” a mythical land where the sun still shines. PW spoke with the duo about being creative collaborators, their long marriage, and what it will be like to tour as co-authors for the first time.

Michael, when did you begin collaborating with Melissa?

MJ: It was only when she took that step into fantasy. I wasn’t involved at all in her chick-lit novels, but I’ve been her collaborator since Blue Bloods. I wouldn’t dare approach the content of her adult books – it’s just so foreign to me.

What was your first involvement with her books?

MJ: Mel and I both read a lot of science fiction and fantasy books. Once she started writing books in that genre, I became interested. She’d come to me with a chapter or a scene.... A big part of the Blue Bloods books is travel. I had traveled more than Mel, who was bound by her immigration status not to travel outside of the U.S. [De la Cruz was born in the Philippines and moved to San Francisco with her family when she was 13, in 1985. After living in the U.S. for nearly 30 years, de la Cruz finally became a citizen last month.]

MdlC: I couldn’t leave the country, and Mike had gone everywhere. The Blue Blood books are all about fabulous locations.

MJ: That was the jumping-off point for the collaboration.

MdlC: And he brought the authenticity. He’d spent a summer in Italy, for instance. I always thought of Blue Bloods as our baby; it just had my name on it. It was kind of organic. I take care of the characters, and Mike takes care of the plotting with me. He also does the world-building and the drama.

MJ: It’s nice to find that natural division, and we do bump heads when we try to work on the same exact stuff.

Michael, what made you decide to “out” yourself as Melissa’s collaborator after working anonymously on all of her previous YA fantasy books?

MJ: Just percentage-wise, the scales tipped towards me. Whereas Blue Bloods was an unequal split, suddenly it was more in the middle with Frozen. Blue Bloods was really Mel’s, and this one is more of me. I had some ownership of it, and it would have been disingenuous to put only Mel’s name on Frozen.

Melissa, do you think your fans knew how much Michael contributed to the other books?

MdlC: Yes. I always talked about Mike when I was on tour or doing interviews.

MJ: The first three or four years I always went on tour with her, so I was there. The publishers knew [of our collaboration], and got to know me really well. But I was always “the husband” on Mel’s tours, and I got tired of it and finally stopped going with her.

MdlC: At the events, my fans would know because when they asked how I came up with certain elements of a book I’d say, “My husband helped me with that.” We were always frank, and it never seemed weird. Listen, I chose him because he was the only guy I ever met who had read all six of Frank Hubert’s Dune books – and was cute [laughs]. I told him, “We’re meant to write fantasy novels together.”

You’ve set Frozen in a futuristic, icy version of Las Vegas and made your teenage protagonist a dealer in a casino. Can you tell us about that?

MdlC: We had a lot of fun building that world. We love Vegas! Anything goes there. I used to go with my parents in the 80s, and the billboards would show women stripping. I was 10 years old and going, “Whoa!” I like naughtiness. Mike and I would go to Vegas every year when we were living in New York.

MJ: We went a little too much. We even went there on our honeymoon. Vegas pushes the edge. It’s a little bit of a fantasy world in itself. It’s not quite real; it’s hyper-real.

MdlC: My cousins are poker dealers in Atlantic City. I love the idea that they’re humble Christian people who are basically card sharks. I’ve always been fascinated by the lives of dealers, the kind of secret life of Vegas.

MJ: I wanted to set Frozen somewhere different. Since it’s a post-apocalyptic story, you can have 16-year-old poker dealers and blackjack dealers, like our characters.

MdlC: I like the fantasy “what if” stuff, like instead of a grizzly leathery dealer you have some bright-eyed kid.

What was your inspiration for Natasha?

MdlC: I was reading Rules of Civility by Amor Towles and really liked the character in it. Her dad was a worker at the docks, and she came from a humble background. But even after she went on to work for Condé Nast in Manhattan and spent a lot of time in the Hamptons, she never hid her background. She was a cool girl, one of the guys but still girly. And she was very confident in herself. I thought, “I want to write a character like that.” I wanted to give Nat some of that slick charm.

How do you divide the writing labor?

MdlC: We talk a lot. There are lots of conversations, and then I usually start writing a one-pager and give it to Mike. He adds a little more flesh to the story, and then one of us will write an outline that we work on a lot. Usually we’ll have conversations for years about a book. Once we have a concrete idea we write the outline, which can take from a week to a month depending on how detailed it is. Mike takes care of all the action sequences, and I take care of all the love scenes [laughs].

MJ: I have an office down the street that I walk to. We used to both work in the house, and it was a complete disaster. There’s no escaping. Here you are at breakfast, here you are at lunch, here you are in the bathroom!

MdlC: And all we were doing was talking about our books. We spent five years talking about Frozen.

MJ: You get annoyed with the same conversation.

MdlC: Also, we’re working partners but we’re also husband and wife, and we’re parents.

MJ: We had to work out who had ownership of a book. There could only be one author in a sense, one person who had final say. But Frozen is a true collaboration.

MdlC: I always had the final say before, because the book had my name on it. Actually, Frozen was the therapy book [laughs].

MJ: And we did work it out.

Since Melissa has been much more in the public eye, Michael, can you talk a little bit about your background?

MJ: I graduated from Columbia University School of Architecture in 1999, and got a job with a firm in New York right away. But then Mel’s father got sick, and we had to move to L.A. very quickly. I took a job with a good firm here, and we did high-end celebrity homes. I didn’t like that very much. It’s a good, lucrative business, but not as artful as the architecture I did in New York. Then I had my own firm, and some great clients, but I liked it less and less. I didn’t see the creativity and the artistic element that made me love architecture, the crazy avant-garde stuff that’s hard to build. The work in Hollywood feels a bit shallow. So I started working in the background with Mel on the books, still feeling dissatisfied, and then took time to brew Frozen. When we sold it is when I shut down my firm. I love architecture and will come back to it in some way in the future.

Any thoughts on your first book tour, coming up in September?

MJ: I’m tremendously excited, because I have this long, weird, shadowy history of the book world. I’ve been to so many festivals and events with Mel, but only as an observer-husband. I think it’ll be cool to actually do it under my own name. It’s a little bit intimidating, though. We did a galley signing at BEA this year, and of course every person who came up just wanted Mel’s signature! I’m like, “I’m signing, too!” A few people started pulling the book away after Mel signed it and I said, “Uh-uh. There’s two of us on this one.”

MdlC: To me it feels like it should have been like this all along, because we’ve been working together for so long. I think it’s fun, and at least we’ll have company.

Let’s pretend the two of you are Penguin sales reps, and I’m the children’s book buyer at, say, Vroman’s in Pasadena. How would you pitch Frozen to me?

MdlC: To me, it’s really a fun action story with a dragon in it. It’s for boys and girls. There’s a love story. It has romance, adventure, dystopia, and fantasy. It’s kind of like our kitchen sink book. I always think, “Go big or go home!”.

MJ: Great books, especially if they’re fantasy, can’t be described quickly because they’re all about the development of a big world and its details. One of the things in Frozen is the food jokes. Ever since I read The Omnivore’s Dilemma I’ve been obsessed with processed food and what it’s done to America and the world. So there’s a lot of deep humor in Frozen about food that lasts 100 years, a world where there are no apples and meals come in aerosol cans or squeezed out of tubes, a world where water is more expensive than gold. These are big issues that fascinate me, that translate into the little details of the world we built for Frozen. It is the zombie-dragon-post-apocalyptic-pirate-slaver adventure. We wanted a big, meaty fantasy novel, and this is it.

Frozen: Heart of Dread, Book One by Melissa de la Cruz and Michael Johnston. Putman, $17.99 Sept. ISBN 978-0-399-25754-4)