Given how much time Russell Crowe has spent in the company of great directors, from Ridley Scott to Ron Howard, it seemed only a matter of time before the actor would put the lessons he's learned to the test by stepping behind the camera.

Perhaps the greatest surprise was how long it took. But by Crowe's own admission, he was waiting for the right film to choose him. The Water Diviner, the story of a grieving father who travels to Gallipoli to find the bodies of the three sons he lost to one of the First World War's bloodiest battlefields, proved to be the script he couldn't resist.

"I put together a project, around 2003/2004, that I was going to direct it, but in a strange way I realised that it was just too easy. It felt wrong," he says. "It was financed in one meeting, everyone was happy with what I wanted to do and it just felt odd. I realised that people were only connected to it because I was a famous b******. They didn't really have any belief that I would bring a particular viewpoint as a director."

With The Water Diviner, things felt different. "I was having the same visceral connection to the piece that I would normally have if I was going to be acting in something. But there was this other thing happening, too, where in some sort of fundamental way I believed that I was the only person who could tell this story in the way that it needed to be told. And that's the sort of arrogance of a director in the first place."

In taking up the challenge, Crowe wasn't just intending to make a war film told from the heroic Australian perspective, but rather an anti-war film that sought to portray the emotional cost of the conflict to both sides - something that he felt had not been attempted before.

"What I had was an experience when I read the script for the first time that was very exciting, but also very embarrassing for me. All the times I've been to Dawn Services, all the moments of silence I've taken to remember the sacrifice that these young soldiers had made at Gallipoli, I had never for a single second spent any time thinking about the other point of view: the Turkish attitude.

"People talk in terms of reciprocal respect, and Turkey's been very generous to Australia and the other countries involved in that conflict in terms of that area of land. It's a national park and our sons are buried there in marked graves. But one of the things you discover in the process is that the Turkish people don't even call Gallipoli 'Gallipoli'. They call it 'Çanakkale'."

Sobering, too, was the difference in perspective shared by both sides. For young Australians, the chance to fight at Gallipoli was the chance to embark on the type of 'adventure' they may never have got the opportunity to experience again.

But for the Turks, the reality was far more immediately brutal, as Crowe came to realise while researching locations in the heart of Istanbul.

"I was in a high school in the middle of town and there were these big clocks which had stopped on a particular time. When I asked if the clocks were broken, they said, 'No, they'd been that way since 1915'. [And that's because ] on a particular day, mums and dads dropped their kids off at school in the morning, and part of the way through the day the government came and took all the senior kids and made them soldiers.

"That's a big difference between people who are voluntarily getting on a boat and going halfway around the world on what they ostensibly think is an adventure, to a nation that is being invaded, that is losing men at such a rapid rate that they've got to empty the high schools of, essentially, children and send them to the front."

It's a point, too, that resonated with Crowe as a father of two sons. He is proud of making The Water Diviner for the effect it has since had on their thinking, as he recalls a recent conversation he had with his youngest about what he wanted to do with his future.

"He said to me that after he's been to school and university, he's going to go and do a couple of battles and when he gets back he's going to get on with his career. When I asked, 'Why would you want to go and do a couple of battles?' He replied, 'money'. And when I pointed out that 'It doesn't really work that way, mate; you don't really get paid that much.' He then said, 'I would have thought you'd get at least a million a battle!'"

His son then asked if his friend could see the movie too. Later, Crowe asked if they had liked it. "They were like, 'yeah, but we're not going to join the army anymore'. So, if I can put a little more truth in their minds and make them see it's not a comic book situation, it's a life and death situation, [and] if all that the whole process of doing this film for three years came down to was showing one of my kids the truth of that situation, then it's still of great benefit to me."

The Water Diviner opens in cinemas on April 3, 2015.