China’s So Long, My Son is three hours long and feels like three years. That’s a compliment. Make it 30 years: roughly the length of this epic, turbulent, stoically harrowing story. A married couple in the “one child” era following the Cultural Revolution lose a son and gain a son — and in turn appear to lose him — through events so intricately tragic that I won’t tarnish them by revealing more.

In 1980s China, family planning was a one-rule-fits-all prescript indifferent to individual lives, loves, needs. Film-maker Wang Xiaoshuai, a veteran of the “sixth generation” (the one following Zhang Yimou and Chen Kaige), set his neorealist thumbprint on Chinese cinema with Beijing Bicycle (2001). He tells stories, impassively styled but never passionless, of plain folk persecuted by socio-politics or social circumstance. The malevolent vision of totalitarianism conspires with the blind artistry of fate.

We feel for nearly everyone in So Long, My Son: even the party-member female foreman, in the factory where the wife works, who orders her to abort a second child. And these two women are friends! They remain so, just about, helped by the former’s gnawing and growing remorse.