Machu Picchu, a co-production by the State Theatre Company of South Australia and Sydney Theatre Company set to open in Adelaide this week, is about a couple involved in a horrific car accident that leaves the husband with severe spinal injuries.

The play explores both the past and present relationship of Paul and Gabby (Lisa McCune and Darren Gilshenan), civil engineers who fell in love at university, share a dream of visiting Machu Picchu, and are now forced to reassess their priorities and rebuild their lives.

Smith describes it as both a grand love story and a deeply ordinary one.

“I intended to write something that would speak to the heart of an essentially middle-class theatre audience to say: this could be you and how would you change your life if it was you.”

Smith is considered one of Australia’s most accomplished writers for stage and screen, with credits including TV’s Mabo and Brides of Christ and the film Saving Mr Banks. She wrote Machu Picchu after being diagnosed with cancer in 2014, just before rehearsals began for Kryptonite, her last play with the State Theatre Company.

Although the new play is not about cancer, she says it is about the things she discovered through having the disease.

“I’ve actually had few years of dodgy health which climaxed with the diagnosis of non-Hodgkin lymphoma … so I kind of found myself thinking about the value of life and how one might reassess going about living it.

“I guess we don’t stop to think about these things because our lives are so busy we just hurtle from one thing to the next; we don’t listen to the signals our bodies and minds are sending us about how we might live a healthier and happier life.

“There were lessons to be learned about life, the value of the moment and the value of finding joy in small things.”

Smith sought out other people living with illness, long-term pain and disability, listening to their stories – some of which she describes as “hilariously funny”.

Writer Sue Smith with State Theatre Company of SA artistic director Geordie Brookman. Photo: James Hartley

Although her own doctor told her he left a Sydney performance of Machu Picchu with his shirt “drenched with tears”, Smith describes the play as a tragi-comedy. She says the humour comes from the characters’ quirks and the silliness of the situations in which they find themselves – including during a visit to an expensive health spa.

“The play also explores Paul’s internal state a bit … he finds himself talking to his inner voices, which manifest in different ways, and one of them is a bit like Elvis. So we have kind of a show-stopping Elvis number in the middle.”

Gilshenan is best-known for his comedic roles in TV shows such as The Moodys and Here Come the Habibs, while McCune, making her State Theatre Company debut, has enjoyed a successful career on both screen and stage, most recently in South Pacific and The King and I.

Smith says that in Machu Picchu, McCune goes through a journey of love, grief, challenge and redemption.

“I think that she does stuff in this play that most people won’t have seen her do – she goes to tougher and funnier and more joyous places than perhaps her television and big stage work has demanded of her.”

The play has been well received in Sydney, and Smith says it has improved over its season there.

“Adelaide is really fortunate because it is picking up a show that is already run in and has found its rhythms.”

As for herself, she has been cancer-free for 18 months, and says her struggle showed her she had more courage than she thought. It’s also clear the things she learned will not be quickly forgotten.

“It just reminds you of the impermanence of life – that you really never know the day or the hour …

“I try to appreciate the small things now; and the kind of big sweeping things sit back into a more comfortable perspective.”

Machu Picchu will have its Adelaide season at the Dunstan Playhouse from April 13 – May 1.