Things I Know To Be True by Andrew Bovell at the Playhouse

Actor Paul Blackwell says, "It came from Tilda Cobham-Hervey's experience."

Left hurt after a break-up, she wrote a list of things she knew to be true.

"She realised it wasn't a very long list," Blackwell says.

This was one of the stories that came out in the development period of the play in Adelaide with Bovell, the cast and a collaboration between the State Theatre Company SA's artistic director Geordie Brookman and British physical theatre company Frantic Assembly's artistic director Scott Graham. Bovell – whose other plays include Speaking in Tongues, which was adapted into the film Lantana – incorporated it into the script. The State Theatre Company SA commissioned Bovell to write the play in 2013.

Brookman says this is the first time he, a text-based specialist, has collaborated with Graham, who is based more in movement theatre, with the aim of learning from each other and working as a team. And the partnership has paid off: Brookman has gone to Britain to help mount a production of the play there.

He says Things I Know To Be True is a drama set over the course of a year that follows the life of an aspirational family in Adelaide's southern suburbs and the changes that take place.

The father, Bob (Blackwell) is retired, while his wife Fran (Eugenia Fragos) still works as a nurse and their four children – Pip (Georgia Adamson), Ben (Nathan O'Keefe), Mark (Tim Walter) and Rosie (Cobham-Hervey) range in age from 34 to 19 ("she's the classic 'accident child'") but, at the start, all still live near their parents and each other in Adelaide.

"They've all been raised to think they can be whatever they want ... but that's not always the case," Brookman says.

He says that sort of encouragement in self-belief was common among his generation (he was born in 1980) by Baby Boomer parents who felt their children were going to have a better life than they had. But, as the parents in the play discover, things don't always work out as expected.

"Things aren't that simple; people are going to go their own way."

The play also contrasts the Boomer generation's "sacrifice now for a pay-off later" mentality with the Gen X/Millennial "have whatever you want whenever you want it" philosophy and shows both can be equally untrue, he says.

"It looks at what happens when the two ideas come into conflict."

So which of these ideas is the truth?

"Search me!" Brookman says. Bovell's aim is not to provide a definitive answer but to raise questions and provoke ideas about the way Australians live and think.

But, he says, while Things I Know To Be True is a sad play, it is also a hopeful one, showing that familial love ultimately can overcome the problems and challenges that life throws at people.

"It's also very funny," he says. There is the humour of recognition of the familiar as people see elements of themselves in the characters and their situations.

"It's full of laughter and there's a lot of tears as well."

Blackwell says his character, Bob, used to work at a car assembly plant but was made redundant at the age of 56. Now 63, he's spent the past seven years looking after grandchildren and tending to his prized rose garden but is now at something of a loose end.

"He feels as though life has passed him by a bit – he's getting over the tedium of looking after the garden."

But he's still close to his wife and his children. If anything, Blackwell says, the family may be a little too close at the start.

"They live in each other's pockets, a bit too smothering, really."

But by the end of the year, things will be very different for everybody, with people's lives going in directions they could never have imagined. And not everyone will still be in Adelaide.

"There are three big crises in the course of the year with each of the older kids that we have to deal with," Blackwell says.

How the family members deal with each of these – a tragedy, financial issues, personal problems – reveals aspects of their characters.

By the end of the year, Blackwell says, "They're still close, probably in a better but certainly in a different way as a result of the events of the play."

Blackwell, who has been a professional actor for 34 of his 61 years, says working with two directors went smoothly as they seemed to be very much in accord on how to proceed. "It wasn't like playing Mum off of Dad and the reverse."

He says the movement aspect was integrated into the text of the play to highlight the emotional sphere and take it to another level.

At Bob and Fran's 30th anniversary celebration, for example, instead of the couple simply engaging in a "cheek-to-cheek" dance, the other cast members lift Fran into the air.

Such techniques are employed throughout the play to expand the lyricism of the speeches, he says, but he himself is never lifted.

"No, I'm too heavy!"

Things I Know To Be True. The Playhouse, Canberra Theatre Centre, June 8 to June 11. canberratheatrecentre.com.au or 62752700.