The last time that Tim Blake Nelson directed a movie that premiered at the Toronto International Film Festival, it was a bleak affair -- and not just because it was a Holocaust story.

Nelson brought "The Grey Zone" to TIFF in 2001, when the festival proceedings coincided with 9/11. This year, he returned to TIFF with his latest feature, "Leaves of Grass," and encountered much more satisfying results.

The movie stars Edward Norton in two roles as sibling rivals. Guided by a strange tone that oscillates from stoner comedy to crime drama, it focuses on Bill (Norton), an established college professor who heads south to visit his brother Brady (Norton in a goofy wig and exaggerated accent).

As the family screw-up, Brady drives Bill nuts with his latest scheme, proposing that they trade places so Brady can evade a debt.

Although the movie received a mixed response at the festival, Nelson told The Wrap that he enjoyed the experience. "It's as film-friendly a festival as there is," he said. "Because it's a larger city, those who come aren't only industry people."

Nevertheless, he seemed a little perturbed by the uncertain future for "Leaves of Grass." "I was hoping to get distribution interest started, and we've done that," he said. "One hopes that the process will go quickly. That simply is not the reality anymore."

But Nelson is content with the finished project, which he wrote with Norton in mind. "The beating heart of the movie is Edward's performance," he said. "The movie succeeds because you get to watch this tremendous actor up there having a blast with an exhilarating challenge."

Despite its offbeat rhythm and sometimes confounding plot twists, the movie does get one thing right: Norton's exchanges with himself are seamless illusions.

Nelson used a combination of motion control photography and other camera illusions, along with digital effects such rotoscoping and split screen, to complete the scenes shared by Bill and Brady.

The actor usually first performed in these scenes as Brady, then switched to Bill and responded to the audio track of his other character. "Edward has this sort of mind where he can map out what the scene is going to be for both characters," said Nelson.

The story came out of Nelson's own experiences traveling around his native stomping grounds as a teenager in Oklahoma. "I considered myself very lucky to be growing up there," he said. "The movie is a menagerie of some of my favorite people I knew."

While Nelson said he did associate with a pair of twins in high school, Norton's characters emerged from a more abstract inspiration.

"Brady and Bill are really version of what I feel I am right now," he said. "Since I'm a filmmaker and an actor, I travel around and do these strange projects, never knowing what's next in my life. I embrace what's unpredictable and unknown. There's little structure in my life, and yet I'm a father of three and a husband of fifteen years. Everything at home is incredibly structured."

Nelson's acting career is busy as usual. He has a role in the Steve Buscemi comedy "Saint John of Las Vegas," which opens later this year, in addition to the pilot of episode of Tim Robbins's upcoming TV series "Possible Side Effects."

He's been rumored to play a part of Joel and Ethan Coen's "Hail Caesar," but Nelson said, "that's something Joel and Ethan are writing. They've mentioned that's something I might be in." Even with his success, Nelson said he remains cautious, a factor he inserted into "Leaves of Grass."

"I think the turn the movie takes is a reflection of my own reality," he said. "Everything can be going so well for you, and then just out of the blue, it can change."