Clayton Zane Comber and Conor McCamman’s new book has come a long way since starting out as an inside joke that they shared while working together.

They will launch their new junior fiction book, The Marvellous Submarine, at The Kiama Pavilion on April 2 at 6.30pm.

The pair first met while working at Clay’s former bookstore-café, Bouquiniste, on Terralong Street. Both dreamed of becoming writers and while working on their individual projects, they accidentally stumbled upon a collaborative venture.

“We just started collaborating, almost as a joke, about this kids’ series we wanted to create,” Clay said. “Somewhere along the way, we thought, maybe this does have legs, so we decided to write it down and expand on it.”

Conor recalls how they would be midway through work at the café, with one person tending to the business while the other wrote.

“We were literally writing it during business hours. One person would be steaming milk and calling over their shoulder, Mr Brains should say this, while the other would be writing it down on the laptop. Or while one of us was sweeping or something. It all just happened in our heads, and we got it down as it came,” says Conor.

The project reached new heights when they figured out Conor had a talent for drawing - after doodling on some of the store receipts.

“Anytime something funny would happen in the shop, Conor would print out receipt paper and draw it like a comic. We had these comics posted everywhere, capturing little funny moments from the shop,” Clay said.

“That’s when we realised how well Conor could draw. He started illustrating some of the book’s characters, so we ended up with all these little bits of receipt paper stuck up around the shop.”

The Marvellous Submarine follows twin siblings who live on an island with their mother, a famous inventor. When their mother is kidnapped, the twins must embark on a submarine adventure with a crew of animals to rescue her. Along the way, they encounter pirates, a blue whale, exploding basketballs, and a host of other ridiculous hijinks.

Collaborating on a book can come with its problems, but Clay and Conor both agree they were perfectly matched when it came to their collective vision for the book.

“There were times when I’d come up with an idea, tell Conor about it, and he’d instantly know how to bring it to life,” says Clay. “He’d draw it, and I’d think, That’s perfect. That’s exactly what I had in mind.”

This is Clay’s second book, following 100 Remarkable Feats of Xander Maze. After finishing The Marvellous Submarine, they handed it to his publisher and agent, and the rest, as they say, is history.

“I had the ability to put the book in the right hands - both to my agent and my publisher - and we were surprised to see how much they enjoyed it,” Clay said. “To the point where I don’t even think they changed anything when we first handed the book in.”

When asked what they enjoyed most about writing a children’s book, Clay and Conor mention the joy of reconnecting with their childlike imagination and creating moments that both kids and adults can enjoy.

“After the release of my first book, I had the opportunity to visit schools and festivals, meeting other children’s and teen writers,” Clay said. “Especially when you’re workshopping with kids, their imagination is incredible. They’re not limited by anything, which as adults, I think we lose a little bit.”

“We tried to make it fun for parents to read to their kids as well,” says Conor. “For example, the pirates in the book turn out to be investment bankers at a costume party on their mega yacht, and they get blown off course and they have to become real pirates just to survive.”

The book will be released on launch day on April 2 and will be available for sale at the Kiama Pavilion, and you can grab a free ticket here.