In taking on an international crisis that’s happening in slow motion, the dissident Chinese artist Ai Weiwei’s documentary “Human Flow” captures the plight of millions of refugees around the world — and does so with images that are by turns disturbing and luminous.
The facts of the refugee crisis are stark. Nearly 66 million people are, at this moment, forcibly displaced from their homes by war, persecution, poverty and the aftermath of climate change. They range from the millions who fled the civil war in Syria to Mexicans and Central Americans trying to cross the border into the United States, from the half-million Rohingya Muslims in fleeing “ethnic cleansing” in Myanmar to the 1.