When Marc Brown, the creator of Arthur, asked longtime friend R.L. Stine, the author of the Goosebumps book series, to make a picture book together, Stine's first response was: Why?
"Marc, you have such a good reputation. Why would you want to do a book with me?" Stine recalls telling his pal.
"He had this inner monster," Stine adds, laughing. "I think you have this inner monster after you do Arthur for 20 years."
Brown got to explore that inner monster and Stine got to do his first picture book with their project The Little Shop of Monsters, a tale about the various monsters children encounter at the titular shop. Illustrated by Brown and written by Stine, the book was released in August.
The partnership is as unlikely as the place where it all began, many years ago: Air Force One, when then-first lady Laura Bush, a champion of children's literacy initiatives, brought Stine and Brown with her to the first Russian Children's Book Festival in Moscow.
It was the flight that launched a thousand pages. Well, 40.
Were they already familiar with each other's work? The question prompted both men, interviewed separately, to reply: Of course.
"Everyone in the world knows Arthur," Stine says.
"He's an icon, c'mon," says Brown. "His books were all over our house, and our kids grew up reading the Goosebumps books. ... They used to come up to the kitchen to read them. They were too scary to read in their rooms."
The children's literature giants have been working in the format for decades. Still, The Little Shop of Monsters marked new territory for both of them.
"You think, 'Oh, boy, a picture book is so much easier to write.' It's not!" Stine says. "It has to be perfect, there's so little text. ... I did six revisions. I never do that many."
For Brown, it soon seemed monsters were the new aardvarks. "I love the idea of drawing monsters," Brown says, "When Bob sent me the final manuscript, I couldn't stop drawing when I was reading it."
"My wife came into my studio and she was looking at the drawings and she said, 'Marc, I think you were born to draw monsters,'" Brown says. "I take it as a compliment. I just had such fun doing them."
About three years in the making, the book was conceptualized before Stine knew he'd be a grandfather.
Now, 18-month-old Dylan has a cameo of sorts in The Little Shop of Monsters: A toy store on the title page is named after him. Brown snuck it in as a surprise for Stine, though the Goosebumps author "didn't notice until I told him."
It's a tradition carried over from the Arthur books, where Brown hid his own children's names in the pictures.
Also hidden in The Little Shop of Monsters' pages? An illustration of a certain Republican presidential candidate best-known for his inflammatory remarks.
With so many monsters to choose from — like Yucky and Mucky, twin monsters covered in slime, and Squeezer and Teaser, who have arms with pinching claws — which would Stine and Brown take home?
Stine's choice: Bubble-Belly Billy, a monster who eats everything he sees. "Do you know what's inside Billy's big belly now?" the book reads. "I hope it's not your friend who lives across the street. (That would be sad.)"
"I was so happy to get that joke in," Stine says. "I didn't know if they'd let me do it."
The Piggler-Gigglers, who giggle the whole day, were Brown's choice. Or the Sleeper-Peeper, whom the book explains as a big hungry monster that "spends all his time sleeping under kids' beds."
"We all wondered what that monster looked like, and here it is," Brown says.
There's another children's book in the future for Stine and Brown, who praised the collaboration as having been a lot of fun.
In addition, Stine's got a Goosebumps movie coming out in October, featuring all of the monsters from the early Goosebumps books and a "much more evil version" of Stine himself, played by Jack Black. And Brown's most recent non-aardvark book, Monkey: Not Ready for Kindergarten, was published in June.
Not to mention a big anniversary coming up: Next year marks 20 years Arthur's been on TV, and 40 years since the start of the books.
"I hope I'm invited to the party," Brown says. "If I'm not invited to the party, I know some monsters I can hang with."