There's a heartbreaking moment early in God Grew Tired of Us that beautifully demonstrates the power of documentary filmmaking. Three young men have just been notified that they will be moving to America from their wilderness refugee camp in Kenya. The men are among the "lost boys" of Sudan; in the 1980s, a civil war forced 25,000 young boys to leave Sudan (and their families) on foot, and they walked more than 1,000 miles to refugee camps in Kenya. Along the way, animals, disease, starvation, and Islamic rebels attacked them until only a few thousand survived. As the film starts, three have been chosen by the International Rescue Committee to relocate to the Unites States.

"What is an apartment?" they ask the filmmakers. "Do people in Pittsburgh go to the river for their water? Shower? What is that? Can you describe it to me?" "I have never worked electricity before," one worries, "so I think it will be very difficult for me to do so."

The subsequent film—which won both the Grand Jury Prize and Audience Award at Sundance—is both moving and inspiring, as we watch the ultimate fish-out-of-water tale turn into one of loneliness and depression, and then again into one of hope. There are heart-swelling scenes of these charming, dignified men trying to maneuver their first escalator, tasting their first packet of butter, flushing their first toilet, and flipping their first light switch.

But nothing in America is free, and they're soon working three minimum wage jobs at once, while struggling with overwhelming separation anxiety, and guilt over their friends and families left behind.

The third act of God Grew Tired of Us loses some of its urgency and focus, which deflates some of the film's emotional punch. But there's little that could diminish the power of watching these young men leave a Third World situation for the land of milk and honey, only to feel a profound loss at the end of the rainbow.