SpongeBob SquarePants, Festival Theatre, Nicolson Street

Nothing, however, could have prepared him for his latest role, which finds him taking up residence in Bikini Bottom, as the loveable cult anti-hero, SpongeBob SquarePants. It's a role that brings the 22-year-old from Consett, County Durham, to the Festival Theatre next week, where he stars in the new musical The Sponge Who Could Fly!

"SpongeBob is great to play," says Coxon, with all the enthusiasm of his cartoon counterpart. "One of those characters everyone would like to be like. He has that optimism and enthusiasm that, especially in British culture, is frowned upon. You're not allowed to have dreams, you're not allowed to try new things – you can do what you want as long as you try to be good at whatever you do. People admire that in a character."

For those yet to meet the little yellow sea sponge, let's dive in at the deep end. The character's origins date back to 1996 when Stephen Hillenburg, a cartoon worker and marine biologist, began working on the concept of an underwater adventure.

Originally named Sponge-Boy, the character wore a red hat with a green base and a white business shirt with a tie.

By the time he made his debut on children's TV channel Nickelodeon in 1999 however, SpongeBoy had morphed into SpongeBob SquarePants as we know him today. A movie followed three years later and by 2007 SpongeBob SquarePants had become the UK's No1 rated cartoon for the 6-14 age group, although he had also built up a cult following among adults and boasted celebrity fans in Austin Powers actor Mike Myers, Oasis' Noel Gallagher and pop stars Justin Timberlake, Britney Spears and Kelly Osbourne.

For all his wide-eyed innocence and popularity, SpongeBob was caught up in controversy in 2005 when he appeared in Sister Sledge's We Are Family video, which was attacked by some right wing groups in the USA as a vehicle for pro-gay propaganda – SpongeBob is a gay icon in America thanks to his lack of inhibitions about holding hands with his best friend, Patrick the starfish.

The furore caused his creator to state: "Everybody is different, and the show embraces that. The character SpongeBob is an oddball. He's kind of weird, but he's kind of special."

As for his relationship with Patrick, Hillenburg said of the pair, "I always think of them as being somewhat asexual."

It's a line that Coxon follows. "I don't think SpongeBob as a character is aware of sexuality. It is not a sexual being – it reproduces asexually, it's a sponge," he says with a laugh, laying the argument to rest once and for all with a piece of undisputable science.

Based on the television adventures The Lost Episode and The Sponge Who Could Fly, the stage musical finds our ever-hopeful hero wishing he could 'fly with the jellyfish of Jellyfish Fields'.

Will SpongeBob take flight or will his dream come crashing down on the ocean floor? Coxon's staying tight-lipped.

"You'll have to come and see to find out," he smiles, admitting that long before he was cast in the role he was a fan of the TV series.

"If I'd been told a year ago that I would be playing SpongeBob today I would have loved it, although I'm not sure I would have believed it.

"It's just incredible to play a character so loved by both adults and children – it's a really nice feeling.

"I was aware of the following he had before I auditioned for the part. Normally for a part like this I would get a few DVDs and do a bit of research, but in this case I already had them, I was already a fan."

The difficulty, he admits, is transferring the magic of an animated series in which anything is possible to the live stage.

"It is difficult because you are trying to recreate this character that is so fluid on screen. For example I'm just getting used to my square costume, although it does have an incredible design, so that, although I am restricted, I can do a lot of the things he does in the cartoon.

"When you draw him you can have him do whatever you want. It's a lot harder when you have to then recreate that on stage."

Especially when that means making him fly.

Festival Theatre, Nicolson Street, Wed-Sat, various times, 16.50-25, 0131-529 6000

be square: Chris Coxon takes up the challenge in Bikini Bottom, together with Patrick Star and his friends

BIKINI BOTTOM ELECTORAL ROLL

SpongeBob SquarePants: A friendly, optimistic sea sponge.

PATRICK STAR: An overweight pink sea star.

SQUIDWARD Q TENTACLES: SpongeBob and Patrick's cranky neighbour.

SANDY CHEEKS: A Texan squirrel, SpongeBob's closest friend after Patrick.

MR KRABS: The miserly owner of the Krusty Krab.

SHELDON PLANKTON: A small green copepod and Mr. Krabs' nemesis.

GARY THE SNAIL: SpongeBob's pet sea snail.