Little Fish director Rowan Woods has not cheered up with his latest film, Winged Creatures.

His first feature, The Boys, was loosely based on the murder of Sydney nurse Anita Cobby, then Little Fish focused on an ex-junkie teetering on the edge of addiction.

Instead of a change to lighter fare, Woods' highly anticipated third film is about a group of people dealing with post-traumatic stress disorder after witnessing a random shooting in the US.

"I was keen to explore more audience-friendly scripts, but ... Winged Creatures was just irresistible," Woods told AAP.

His first US film, Winged Creatures came to Woods from producer Robert Salerno (21 Grams), who was deeply touched by the multi-storyline drama by Roy Freirich.

"(Salerno) related his feelings about September 11 and how the script resonated for him of the sort of trauma that he saw and experienced around him in New York City," Woods said.

While there had been many films exploring the trauma of post-September 11 America, Woods said this film took the themes further.

"I think Winged Creatures goes way beyond those sort of issues in previous films because it actually more directly addresses the consequences of violence in American society, particularly in relation to guns," he said.

"But the thing about the script is it does it in a very clever, covert way and you're never aware of the fact that it's a political script, or it's a hot social issue.

"It's just a deeply affecting personal story about these ordinary people, ordinary Americans, who are the victims of horrible gun crime."

Woods found many doors suddenly opened to him in Hollywood because of Cate Blanchett's starring role in Little Fish, and it allowed him to again attract an all-star ensemble cast, including Forest Whitaker, Guy Pearce, Kate Beckinsale, Dakota Fanning, Jeanne Tripplehorn and Jennifer Hudson.

Whitaker and Beckinsale were the first to sign on to the film, and once they had the rest was easy.

"With Forest and Kate on board all of the other actors began to swarm around the project," he said.

"It was a very very exciting time."

One of the toughest and most complex roles in the movie went to Hollywood starlet Fanning (War of the Worlds), who was just 13 at the time.

"Dakota was looking to transition out of child-like roles, so it was a huge thing for her," he said.

"In the climactic scene, which is really a scene between her and (her 12-year-old co-star) Josh Hutcherson, she had to deliver in a very gut-wrenching emotional way that most mature-age actors would be very nervous about, and she just knocked the scene out of the park.

"You just look at Dakota and Josh and the way they stand up in this movie compared to all their other films and it just takes your breath away."

Winged Creatures is due for a March 2009 release in the US with Australia to follow.