LOS ANGELES — From best-selling authors Rick Riordan and Mark Oshiro comes another Nico di Angelo adventure novel, “From the World of Percy Jackson: The Court of the Dead,” marking their second collaboration.

It picks up a few months after “The Sun and the Star” left off, with demigods Nico di Angelo and Will Solace joining Nico’s half-sister Hazel Levesque on the West Coast. There, Hazel needs help assisting a group of refugee monsters who have taken up residence at Camp Jupiter. The demigods realize a mysterious dark force is at work when the monsters begin disappearing from camp one-by-one.

On The Red Carpet got the chance to chat with the authors about the development of the sequel, Riordan’s story essentials, Nico and Will’s relationship and their upcoming book tour.

When it came to conceptualizing “The Court of the Dead,” Riordan told us it all began with his first “Percy Jackson” novel.

“It started with a joke about where the Minotaur gets his underwear, his tighty-whities that he famously wears in ‘The Lightning Thief.’ And we thought, you know, ‘what if he like, knits his own, and why would he do that?’ And then that got us into this whole tangent about, ‘who is this Minotaur, and why does he enjoy knitting?’ And Mark really was the one who took that kernel of an idea and turned it into something viable and something really vibrant,” Riordan explained.

Oshiro jumped on the idea, saying, “I don’t think I even told anyone when I had the idea. I just wrote it down in my notes app of what if the Minotaur shows up at Camp Jupiter and is like, ‘yo, Hazel, I need some help.’ What would he be asking for help and what would Hazel’s reaction be?”

Oshiro elaborated on their development process.

“What is it about Nico and Hazel that either hasn’t been explored directly, or is like, (what) they have in common? And it’s that both of them deeply dislike being judged. And every instance we’ve seen them being judged in the series, they have very strong reactions to it. And I love this idea of what if they have a story that is about them and other characters being judged?”

“The Court of the Dead” sees a more “subtle” examination of Nico and Will’s relationship, Oshiro told us.

“‘The Sun and the Star’ was about their relationship existing and what happens when it’s challenged by these outside forces. And so, this book our challenge was that one, we didn’t want to repeat ourselves – but I actually think there is little to no strife between Nico and Will – But instead it’s, how do they keep going on and what happens?”

Before Oshiro could drop any spoilers, they acknowledged that “Nico is on a very particular journey with his mental health,” in this book. “Will is learning, ‘how do I actually support this person?'”

Riordan has written over 20 stories as a part of the Camp Half-Blood Chronicles, appealing to audiences who grew up with the series and new readers. We asked Riordan what goes into keeping his books accessible to readers of all ages.

“I try to create a story that I would be comfortable and happy telling my middle school students back when I was a middle school teacher. So it’s gotta be relevant. It’s got to be fast paced. It has to be fun and funny. But there’s also got to something real there, something they care about, something that speaks to them,” said Riordan. “If I can make a story that appeals to that very difficult audience of middle school kids who have so much else going on and so many other things pulling at their attention, hopefully it will also appeal to kids that are younger and kids that are older and adults.”

To celebrate the novel, the pair will be traveling around the U.S. for a book tour.

“Oh, I’m so excited,” Oshiro exclaimed. “You know, we try to design a show that is entertaining and silly, and it does have an element to it that is chaotic, where we get to answer questions from the audience and whatnot, so that it does have a unique feel to it. And so what I’m most excited for and what was so fun about touring for ‘Sun and the Star’ was getting to see fans’ enthusiasm.”

If you’re thinking about cosplaying your favorite character, Oshiro is here for it!

“Getting to see how much these characters in particular mean to people and the number of cosplayers of Will and Nico- And now I’m excited to see Hazel cosplayers, hopefully,” they said.

Riordan is just excited to see fans. “It really is sort of a feedback loop of good feelings and Lord knows we need those these days. It’s nice to see so many people come together just to celebrate reading.”

“From the World of Percy Jackson: The Court of the Dead: A Nico di Angelo Adventure” hits shelves September 23.

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