Over the weekend, a 143-minute documentary criticizing China’s environmental policy went viral in China, accumulating nearly 100 million views on popular Chinese video hosting sites since its release online on Saturday.

In “Under the Dome,” former Chinese state TV broadcaster Chai Jing weaves together her concern for her infant daughter, who was born with a benign tumor that required surgery, with China’s reliance on fossil fuels. The documentary arrives just days before China’s annual National People’s Congress, where pollution is at the top of the agenda, and has met with widespread praise from ordinary citizens and governmental officials alike. Chen Jining, China’s new minister of environmental position—who only took his post last Friday—praised the documentary as China’s Silent Spring, Rachel Carson’s seminal 1962 book that ignited America’s environmental movement. 

“You don’t have any choice about breathing. There’s no way to avoid it,” Chai tells the live audience in the documentary. “To be honest, I’m not afraid of death. I just don’t want to live like this.” 

In one particularly harrowing scene, the camera follows the surgery of a 50-something lung cancer patient. The woman was not a smoker, but the piece of lymph node the doctor removed was thoroughly black. 

Despite the buzz, the documentary comes as less of a surprise given China’s dramatic shift on pollution in recent years. As recently as 2011, state media still blamed “fog” rather than smog for poor visibility in China’s cities, and state meteorologists insisted “heavy fog” was “a normal climate condition in Beijing.” As denial became increasingly untenable, the Chinese government has taken action, signing a historic climate deal with the U.S. in November last year and cutting emissions at home. Since the government has taken action on pollution, it’s become an issue Chinese citizens are permitted to complain about. Chai herself is no dissident. A former state TV reporter, she likely cleared the documentary with important figures in the government before releasing it.

The government has not allowed the criticism to go unchecked. The Wall Street Journal reported that China’s propaganda authorities told media outlets on Sunday to stop covering the video and to pull existing articles from their sites. The documentary itself remains online. The Chinese government frequently aims for this delicate balance between allowing criticism and preventing widespread dissent. In August 2014, a Harvard University researcher found China's Internet censors, who may number up to 250,000, do not screen for all criticism, but clamp down on speech with "collective action potential"—that is, any content that may mobilize mass protests in the real world. The same rule applies for "Under the Dome."