Caton plays larrikin Broken Hill taxi driver Rex, who is diagnosed with terminal cancer and sets off on a journey to Darwin to find crusading euthanasia advocate Dr Nicole Farmer, played by Jacki Weaver.

During his epic road trip through some of Australia's most breathtaking country, he comes across Tilly, played by Mark Coles Smith, a young Indigenous man who tags along on the journey north.

Caton and Director Jeremy Sims were in Canberra on Sunday to promote the film, as they reached the end of a six-week stint of screenings.

The film's examination of racism through Tilly and Rex's neighbour and love interest Polly, played by Ningali Lawford-Wolf, comes at an important time, as the treatment of Adam Goodes continues to bring issues of race and discrimination to the fore.

"Isn't it prescient, in terms of what's happening now, what the discussion is at the moment?" Caton said on Sunday.

The film balances the heavier territory like euthanasia and racism, with humour and warm-heartedness.

Sims said storytelling, whether through film or other mediums, remained a powerful way to confront and challenge audiences on such issues.

"Everyone who has got an opinion on the Adam Goodes story should go and watch this movie, I reckon, because they'll have a slightly different view by the end of it," he said.

"And of course the film doesn't answer any of those issues. It's not like you can watch the film and know what to do.

"But it does present Tilly, and it does let you know how hard it is for young Aboriginal men whose culture and law disappeared five generations ago."

The pair were at a screening at Dendy Cinemas in Civic on Sunday night.

Caton said the film's reception so far had been fantastic.

"It's exceeded our wildest expectations actually, the feedback has been great," he said.

The stunningly captured outback in central and northern Australia takes on its own life and becomes a major character of the film, according to Sims.

"It was enjoyable to see it, it was sort of less enjoyable to drive it with 18 vehicles and 35 people," he joked.

"But it's why we went. It's why we actually did the drive.

"Sometimes you just turn the camera on and you just walk away and you know it's going to be a good scene just because the scenery is just so extraordinary."

The film is due for release at cinemas across the country later this week.