Cassandra Clare has sold 50 million books, but the thrill of a first bestseller? Unmatched

Midway through my conversation with Cassandra Clare, there’s an interruption.

Her husband has been waving his arms, frantically trying to get her attention, she says on the phone. “Guess what? I’m number one on The New York Times series list,” the YA author tells me when she deciphers what he’s mouthing to her, referring to her newest book, Chain of Thorns, which had come out a few days earlier. (The book is also No. 1 on The Globe and Mail bestseller list.)

It’s all very exciting, but it’s hardly the first time the U.S. writer has made a bestseller list. In fact, she has been topping charts since her debut novel, City of Bones, hit The New York Times’ chart at No. 7 and The Globe’s chart at No. 4.

“My book had been out for a week, and I was at home, sitting on my sofa, working on the second book in the series,” says Clare of the moment she found that news out. “My editor called me, and told me, and I was just stunned.”

She remembers sitting for a moment in total silence – this had never entered her mind as a possibility, she says – and then she called her mom.

“She’d always been so supportive of me as a writer, and I wanted to let her know it had not been a mistake to encourage me to follow my dreams,” says Clare. “Then I called my father, who’d always been behind me saying, ‘You can always go to business school, it’s not too late,’” she continues, laughing. “I’ve hit bestseller lists since then, I’ve hit milestones, but there’s nothing quite like that first time,” she adds.

Practically, she says, it meant many more people would encounter her books because stores often order based on what’s on the bestseller lists, a nod to the self-perpetuating way that being a bestseller makes you a bestseller.

The intricate worlds Clare creates at her desk in western Massachusetts blend lore, magic and romance in a way that captures both teenagers and adults alike. Her writing has been translated into more than 35 languages, and her Mortal Instruments series has been adapted for film and as a series (streaming on Netflix), which was, fun fact, filmed primarily in Toronto.

It’s somehow all the more incredible when you consider that her books, aimed at age 14 up, easily average more than 500 pages, and her latest comes in at an astounding 778 pages.

Not bad for someone who started out writing fan fiction and chose a pen name – she was born as Judith Rumelt – mainly out of fear that people would struggle to get her birth name right. (In fact, most people call her Cassie these days. “It’s a personality I’ve grown to inhabit,” she says.)

The Globe talked to Clare about being a bestseller, why she’s drawn to writing YA and how she keeps all her stories straight in her head.

You’ve sold more 50 million copies of your books. How do you even quantify a number like that to yourself?

I don’t think you can. For me, probably 60 per cent of my sales are not in the U.S., so those are worldwide numbers. You know, my mother went to Poland, tracking down our heritage trying to find where our family, who were Polish Jews, came from. She was on a train, and she looked across the compartment and saw two teenage girls reading my book, and immediately interrupted them to say she was my mother. To me, that’s what it means, that interaction where my mother was in a place where she thought there would never be a chance she would encounter somebody reading my books – but they are bestsellers in Poland, and Brazil, and Germany.

The world-building in your books is layered and intricate. How do you keep track of it all?

For a long time, I had a wall with notes and character cards, and the characters were connected to each other by different coloured strings, which meant things like, ‘enemies,’ ‘lovers,’ ‘family.’ At some point, my friend came over and said, ‘You’re a writer, not a serial killer.’ I remembered having been in the offices of Simon and Schuster, and looking at what they call the “story bible” for a series of tie-in books for Buffy the Vampire Slayer.

I thought, well, I should do that for my own books, because it has all of the information about the book written for someone who didn’t know it that well. Now, I have a story bible that has sections for “history,” “weapons,” “family tree” and the characters, down to how they look, even minor things like scars they’ve gotten. It’s also the background to what the characters know, because there are a lot of secrets floating around the books.

In the time that you’ve been writing YA, our perception of the genre has changed a lot. It’s become much more normalized for someone, say, in their 30s to read books that are technically aimed at 14 year olds.

When I was younger, what we had that was called “young adult” was a very different kind of genre. It was a mixture of what I would call “problem novels,” intended to help kids cope with some kind of issue in their lives, like eating disorders, abuse, grief. There were some that were considered historical, like Johnny Tremain by Esther Forbes, and then a little bit of fantasy, which I devoured. I feel like there’s been a sea change from YA largely being a school and library driven kind of book into it being a real commercial field. There’s a lot more books that are fun and are just good storytelling. It’s completely normal for people in their 30s and 40s to read YA and enjoy it. People have realized that just because a book is about teenagers doesn’t mean it is only for teenagers.

For you, what makes a book a “young adult” book?

It largely has to do with the concerns of the characters. You can write a book about teenagers that’s not a book for kids. I’ve just recently written my first adult book, called Sword Catcher, a Game of Thrones-type adult fantasy [out this fall]. For me, the challenge when I was writing it was having these characters suddenly have these relationships, and the concerns of the characters are suddenly different. When you’re writing YA, the characters have a certain attitude to their parents, which is “parent, child.” When you’re writing adults, you know your parents not just as the person who takes care of you, but as a normal, whole human being like you. Instead of writing about first love, you’re writing about people that have loved before. It’s things like that which denote to me that’s an adult book.

Do you find it easy to get back into that teenager mindset?

I do, and I don’t know if that’s a good thing or a bad thing. I love reading YA, I love teen shows. There’s something about that time period in my life where I feel like it’s very close to me. It feels like it was yesterday. I can reach back into that time, and think about how it felt when the first crush you had felt like it was the biggest love that anybody had ever had, or a let down was the most crushing disappointment ever.

Chain of Thorns is the end of a trilogy. How do you feel about ending a series?

It’s always a time of sadness, where you’re wrapping it up and putting it aside. The only way for me to get past that is to start something new. I’m always working on more than one thing at the same time – when I finished Chain of Thorns, I moved immediately onto finishing Sword Catcher. And I never say never. There’s always the possibility of a short story or a novella or way they’re going to appear in another book.

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