Lixin Fan's documentary "Last Train Home" opens with this fact: The world's largest human migration occurs at Chinese New Year, when 130 million workers leave their urban factories and return to their rural hometowns.

Lixin Fan's documentary "Last Train Home" opens with this fact: The world's largest human migration occurs at Chinese New Year, when 130 million workers leave their urban factories and return to their rural hometowns.

Fan, though, is only interested in two, husband and wife Zhang Changhua and Chen Suqin. They toil every day in a dingy factory in Guangzhou, just so they can spend their only time off fighting for train tickets and traveling more than 1,200 miles to see their kids in Sichuan, even for just a few days.

The film suggests that this kind of separation is common in China. Kids stay with their grandparents while their parents travel across the country to find work.

This system hinges on the hope that the kids become successful and can then care for their overworked families.

Restless daughter Qin, however, has lots of anger toward her absent parents and little interest in finishing school. By the time the next New Year migration comes around, Qin is working in the factories, too.

Fan's natural style allows us to observe and empathize with this fracturing family, even when it becomes clear that they are not headed for a happy ending.