If you're unsure of who the Gruffalo is, well, he's the title character of a very popular children's book. It features a mouse doing his best to avoid being eaten by a fox, an owl and a snake.

He does this by inventing a fierce-sounding character to scare off each of the predators. But then he gets the shock of his life when he finds his fictional creation is very much real.

And his creation is, of course, the Gruffalo. But the beast and McRae had never crossed paths.

"I had no idea about it," McRae says.

"I think I'd seen the cover before but I'd never read it. I didn't really know much about The Gruffalo at all."

So he made sure to read all 693 words before auditioning and kept reading it after he got the role too.

"In rehearsal we were looking at it a lot," he says. "It was a lot to do with the pictures and what they tell you from a character point of view - getting to know what they're like.

"So the Gruffalo, even in the pictures of him, there's that almost a kid quality to him. Yes, he's portrayed as a big monster but there's this unknowingness to him that makes you think he's an adolescent Gruffalo. That he's sort of working himself out as well."

A book that contains just 693 words would make for a very short stage show - which is why the live performance adds extra detail, including singing and dancing.

"The main thing they've allowed to grow is the predators, so each predator has their own song and the character has been pulled out a lot more," McRae said.

"And then with Gruff, there's a song for him as well.

"I think it's more about creating a story around the story to fill it out. All the lines that are in the book, we use but then it'll come to a certain point and that will be a jump-off point to then create something new and then come back to the story."

Bringing a story that is so well-loved to the stage might seem a frightening proposition. After all, children know the story so well and they can be very honest critics: if they don't like what you're doing, they will let you know.

But for McRae, that familiarity is a great thing.

"I think that's the greatest part about it because you're not walking into an audience who doesn't know what the story is, which is the [case in the] majority of stories that you do," he said.

"You're making sure that the audience is up to speed with what's going on in the story.

"It's actually quite nice to have a whole audience who are completely ahead of the story and, when you get to certain parts, they join in on the storytelling.

"I really like that part of it."