A short film shot in the streets of suburban Dandenong in Melbourne's east has been selected for official competition at the prestigious Cannes Film Festival.

All These Creatures is about a 13-year-old boy trying to piece together an image of his destructive father while coming to terms with his own fears about what sort of man he will become.

The film was one of eight selected from 3,943 entries in the short film category for this year's festival on the French Riviera.

Writer and director Charles Williams said he went through the unusual process of writing a short film where the personal characteristics of the lead character were essentially left blank as he searched for the perfect actor.

"There was a very specific thing that I was looking for from the lead role," he told ABC Radio Melbourne's Rafael Epstein.

"It's tough to find a kind of maturity and an innocence that comes across visually in a film.

"In order to give myself the widest selection possible, I just left it open to the gender and the race. I didn't think these things mattered that much with this story.

"I knew I could rewrite the essence of the story around the right person if I found the right qualities and the right dynamic between the parents."

Writer and director Charles Williams said gender and race weren't important in casting. ( Supplied: Mathew Lynn )

Williams considered about 400 children for the lead role and his final round of casting was as diverse as Australia itself.

"We had a boy from Scotland, we had a girl who was born in Australia but her parents were from Zimbabwe," he said.

"We had a whole range of kids, but we eventually settled on Yared Scott, who was born in Ethiopia and raised by his adoptive parents in Melbourne.

"He had actually had some [acting] experience, which I was surprised at; I thought most likely I was going to find some kid out of the blue."

After selecting the lead actor, Williams went about rewriting the film.

He brought on a number of advisers from Melbourne's Ethiopian community to ensure the film was truthful and sensitive to their culture.

"What was truly surprising was that each of these advisers were certain that the film was written specifically about Ethiopians.

"They were sure the way the characters behaved and the social code around issues like mental illness and repression and shame were uniquely theirs.

"It was a lesson in the universality of stories that are truly personal."

Williams said the streets of Dandenong also gave the film an authentic backdrop.

The film looks at the social code around mental illness. ( Supplied: Emma Buglisi )

"Dandenong ... is one of the most interesting parts of Melbourne. It has a really vibrant, not just multicultural community, but it's also incredibly diverse visually," Williams said.

"We set the film in the mid-'90s and there were some areas where you could get something more dated and there were some areas that weren't as gentrified as other parts of Melbourne."

Williams, who has had films screened at more than 50 international film festivals, said being selected to premiere in official competition at Cannes was "probably as good as it gets" for a film.

"I can't think of a higher honour for me."

Williams credited the City of Greater Dandenong for supporting the project.

The council's corporate services director Mick Jaensch said the film tackled the complexities of mental health head on.

"What began as a project in raising mental health awareness in our own community will now have the opportunity to have an impact internationally," he said.

"The end result has exceeded our expectations."