Shine director Scott Hicks's film follows Owen's sports writer Joe Warr as he loses his second wife to cancer and is faced with looking after his two sons alone.
"Everytime I read the scene where I say to the little boy, 'Your mum may not be around much longer,' I used to cry," Owen said. "Just the idea of having that conversation I found really upsetting. Sitting down with a kid and saying that is deeply upsetting."
Owen told DS that he felt it was important to establish trust with co-star Nicholas McAnulty, who plays his youngest son Artie, before filming started.
"I got out to Australia early and all through rehearsals there was Clive and Nick time scheduled in, which was we go off and do something together," he explained. "It was important, he had to trust me. It's important that he felt safe when we were doing some of the tougher scenes - that he didn't think it was me going weird on him."
> Click here to read our full interview with Clive Owen