But first, they had to survive a great and unusual adventure filled with brutes in nail polish, a strange bookshop, a child-eating beast, a very bad orchestra, flying chunks of cupcake, a talking fox and swords, with a wickedly entertaining baddie who has a lot to say for herself and a rather weak stomach.
Now Isaac’s second book Zola the Roller is about to hit the shelves, and – although he can’t officially say it – he thinks it is better than Queen of Muck.
This one is a page-turning action tale full of laughs, thrills, incredible twists, suspense, orphans, opera singing, danger, a greedy villain, bravery, sad bits, scary bits, extremely poor supervision and one of the greatest finales you may ever read.
Life’s pretty okay at the St Alice home for orphans. Until someone dastardly decides he wants to ruin everything.
How will Zola and her friends stop him? What’s behind that door? Why is the doctor acting so strangely? Who’s in charge of these kids? And… wait, where’s that music coming from?
Isaac says Zola was easier than Queen of Muck in some ways because he knew what was coming – but the writing was more demanding because he paid attention to things such as how to write characters, pacing the story and how to treat action scenes and emotions.
“I actually studied all that stuff at night to make sure I was getting it right and wrote during the day,” says Isaac.
“I really put myself through the mincer, but it was great.
“I really enjoyed Zola, because the characters and their adventures kept me on the hook all the way through.”
This included creating Fabiano Berettoluzianicino, the world’s greatest opera singer, poor little Henry Pignut, and dastardly Mr Snide, the greedy property developer.
“And Zola, of course. She’s the kind of kid I would like to be… except for the orphan bit.”
Isaac says life as an author is a bit all over the place – but he likes it that way.
“My background is as a creative writer in advertising, where things move at whiplash speed all the time,” he says.
“You have to come up with something great by tomorrow or there won’t be a tomorrow.
“That’s how I like to work. I’d rather lurch right in and throw everything at it for a shorter time than go dipping in and out, pushing ideas aimlessly around the plate for years.”
And he enjoys the journey - but especially the last half, when you have the general story down and characters in the bag and you’re just making it sing.
He says seeing the illustrations come to life is exciting, and then getting the advance copies is fantastic.
“Then you have a book. It exists.”
Isaac says his go-to writing method is to pick one of the many ideas he comes up with and just start writing any old rubbish.
“Eventually, the real story will appear - usually after a few thousand words.
“Zola the Roller ended up totally different to the story I started, and much better.
“And the big finale didn’t arrive until I was almost halfway through the first draft.
“It’s more exciting for me this way, and definitely seems to make for a more unexpected story.”
Isaac thinks a lot of writers don’t finish because they come up with just one grand idea and then start writing, and often that grand idea turns out to be unworkable and no fun anymore by chapter three, so they quit.
An important part of the process is when Isaac’s wife Kim reads the finished manuscript aloud to see where the holes and weak bits are.
“It usually takes two days, and if anything sounds wrong, I have to fix it on the spot,” he says.
“It’s a real grind.”
But Isaac’s books are hits with kids, and that is what is important to him.
“Childhood is supposed to be magical, exciting and fun, but these days it seems like kids aren’t allowed to forget for a second that they might be anxious or feeling bad about something.
“My books are designed so kids can get those thoughts out of their heads and live.”
Q. What are some simple ways we could all make the world better?