Showbusiness is a roll of the dice: you never know what's going to be a hit, or a flop. Even Riverdance supremo Moya Doherty admits to being in the dark when it comes to predicting how to nail a sell-out show.
"It's a high-risk business and you never know what's going to be a hit or a miss," she told the Herald. "You need to be fond of heights in this industry – that's for sure."
Moya has had a career of overwhelming highs; Riverdance has been seen by more than 22 million people in 350 venues worldwide.
But there have also been lows; in 2007 the The Pirate Queen, based on the adventures of Grace O'Malley, sank without a trace after a brutal Broadway run.
"There is no scientific theory to making it work," the mum-of-two said.
"If there was, everyone would be at it. You just follow your instinct, get the best people you can and keep your fingers crossed.
"It's like telling a story," she said. "You never know how the story is going to turn out until the most important component comes in – the audience. They are the ones who tell you in the end whether it worked or not."
Riverdance is without a doubt the most successful stage show to come out of Ireland. It has played to a global television audience of two billion and more than 5.5m pounds of dry ice have been pumped out during its 20-year run. Moya believes it was the Irish music and beat of hard shoes that contributed to its success.
"The secret of Riverdance was we took a cultural and traditional form from the backroom and put it in the mainstream.
"The pounding of the feet is reminiscent of the pounding of the heart. And this speaks to the audience.
"And so does Irish music. I always say Paddy Moloney of The Chieftains discovered China well before we did.
"Also, we mixed the Broadway chorus dance with Irish dance. Until then Irish dancing had just been competitive – people had never seen that level of synchronicity and unity."
John and Moya are currently auditioning for their next big-budget dance show which will be called Heartbeat of Home.
The dancers were chosen via an online talent call and yesterday showed off their fancy footwork for the couple.
"I'm quietly confident – we have a great creative team behind us. Joseph O'Connor wrote the lyrics and everyone involved is at the top of their game. So I've a good feeling about it."
The show will open in the Bord Gais on October 2 and it will run for at least 21 performances.