So too did long-term Parkes Musical and Dramatic Society performer and life member Bill Jayet in his 56-year theatre career.

In the final performances of Wicked, every director's nightmare came true.

On Sunday, May 16 leading lady Hannah Symonds, who played Elphaba, suddenly fell ill halfway through act two.

Thinking she had eaten something that disagreed with her, she soldiered on to finish the show, but during the course of the week that followed, she couldn't hold any food down.

After seeing a doctor by Wednesday, who recommended bed rest, electrolytes and plenty of fluids, she was no better come Friday but made the decision to take the stage.

"Although very weak, she managed to push herself through the show and we all felt a little more confident for the weekend," Lyn said.

Her illness hit her again with vengeance on Saturday but not wanting to let anyone down, Hannah was determined to take the stage.

"As her situation was quite precarious, we made the decision to warn the audience at the start of the show," Lyn said.

"She soldiered through the first act, but the demands of flying high in a harness and four layered dress while belting out 'Defying Gravity' brought her unstuck and she collapsed."

Lyn took her to hospital while the audience was informed what had happened, the cast devastated and understandably worried about Hannah's health.

Mindful of the audience waiting for the show to continue, Society members decided to perform snippets of act two that did not require Elphaba.

But then something extraordinary happened, not once but twice.

"As many know, amateur societies cannot understudy a huge role like Elphaba," Lyn said.

"Finding one person who can sing the monster songs is hard enough, finding two is impossible.

"Plus the role is so big, you cannot commit a cast member to learning it when the chances of them ever playing it are very slim."

A former Parkes M&D member and performer was in the audience that night.

Hannah Farrant-Jayet, Bill's daughter, stepped on stage in costume to sing 'For Good' with other leading lady Shannen Toole, who was Galinda - Lyn describing the moment as a real highlight of act two.

Hannah had previously recorded the song for her late mother Lindy Farrant.

"Emotion ran extremely high with many of the cast in tears at the loss of Elphaba Hannah, and the beautiful performance by patron Hannah," Lyn said.

"Everyone in the audience for this historic show agreed they had just witnessed something very special and acknowledged it with a standing ovation."

By Sunday Lyn said it was very obvious they weren't going to have Hannah on stage.

"Knowing we had people who had travelled from as far away as Perth, I was keen to put on some sort of show for our patrons, even if it were a concert version," she said.

Then came a phone call at 9am from another former M&D member who was back in Parkes from Sydney to watch the show, an opera singer herself Jessica Westcott, daughter of musical director Neil Westcott.

"Being an avid Wicked fan, Jess knows all the songs and offered to help in whatever capacity we needed. We decided we would do the show proper and she would simply hold a script, for lines," Lyn said.

"We rehearsed from 10am to midday and by 2pm Jess was greened, costumed, wigged and ready for the biggest challenge of her life.

"Again, we made an announcement to the audience, and the show went on.

"Jessica pulled-off undoubtedly the most difficult role in musical theatre, barely missing a line, without singing a bad note, belting out a performance that left us all shaking our heads.

"The cast, crew and production team are so very thankful to Jess for giving us the opportunity to enjoy our final show and put Wicked to bed on a high.

"What happened on the last two shows of Wicked will go down in theatre folklore and no doubt, will be talked about for many years to come."

That aside, Lyn said the Wicked season sold to 96 per cent capacity.

"After 14 months of waiting, it was so amazing to finally have our season. I guess you could say the show was...Wicked!" Lyn said.