Is it possible to capture one day on earth in a single movie?
Last summer, Macdonald and executive producer Ridley Scott asked anyone who was willing to grab a video camera and record their lives on a single day, Saturday, July 24. Over 80,000 clips -- some 4,500 hours of footage -- were uploaded for the project, coming from 192 countries.
The submissions have been edited into a 90-minute film, which premiered at Sundance and streamed at YouTube.com.
"The actual amount of really strong stuff is enough to make a 24-hour film," said Macdonald, who directed the 2006 film "The Last King of Scotland."
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Macdonald and a team of film students combed through the clips, tagging them by subject and rating them on a star system -- 1 star for the worst, 5 for the best, and 6 for clips so bad that they were good. The raw clips have been posted to a YouTube channel where anyone can browse videos through maps and keywords.
The videos, shot on everything from cell phones to professional cameras, document the remarkable diversity of the globe -- births, deaths and everything in between, from the momentous to the mundane.
"I'm not saying it's all fantastic," Macdonald said. "There's a fairly large amount of narcissistic, boring teenage rants."
But there's also plenty of beauty. The organizers distributed hundreds of video cameras to some of the most remote corners of the globe -- deep into rainforests and remote regions of Africa.
In choosing which footage made the final film, Macdonald said, they looked for honesty and intimacy above all else.
Soma Helmi, a filmmaker from Bali, Indonesia, recorded her housekeeper as she made prayer offerings in a lush garden.
"In the beginning, you just upload your footage and you don't know where it's going," she said. "You just know that there are thousands of people doing the same thing."
All told, the finished work includes material from over 450 contributors, each of whom has been credited as a "Life in a Day" co-director. Twenty-six of the contributors from around the world were flown to Sundance to attend the premiere and meet one another.
The group includes people from Kathmandu, Kabul and some closer to home. The Liginski family -- Bob, Catherine and young son Bobby -- came from their home in Grayslake, Ill. The film includes gripping footage of Catherine's emotional struggle with breast cancer.
"That was the day after she came home from the hospital," said Bob Liginski. "She had a double mastectomy and reconstruction, and tubes coming off of her that she had to drain."
The Liginskis have now met some of their co-contributors and say they can't wait to see their story on the big screen.
"It almost feels like it gives everything we went through a positive meaning and even a bigger meaning," said Catherine.
As Macdonald pieced together the film, he said he was struck, not by the differences between people around the globe, but the similarities.
"Fundamentally, we're really only interested in the same things, which are children, loving our family, getting old and dying," he said. "That's it really, not much else to think about."