Chai Jing (柴静) was a former anchor and journalist who became a household name through her in-depth investigative reporting for China Central Television of national news stories such as the SARS outbreak, Wenchuan earthquake and coal mine accidents.
Having taken time off to have a daughter she ended her self-imposed exile with a self-funded documentary about smog called "Under The Dome."
Gruesome pictures of withered trees, murky skies and lifeless rivers appear but the film also shows a scientific perspective backed by data, field investigations at home and abroad and interviews with officials, scientists and the general public.
Beijing had 175 polluted days in 2014, eclipsed by neighboring Tianjin with 197 and Shijiazhuang with 264 days.
Satellite pictures from NASA demonstrate worsening air quality in northern China over the past 10 years.
Chai, again exhibiting her skills as a story teller, illustrates these statistics by taking the examples of tearful babies battling pneumonia, caused, according to their mothers, by bad air and a woman in her 50s undergoing surgery at Beijing Cancer Hospital.
The burning of coal and oil contributes to 60 percent of PM2.5 pollutants, or airborne particles smaller than 2.5 microns in diameter that penetrate the lungs, building the statistical background for her to question the country's energy consumption habits.
China burnt 360 million tons of coal in 2013, more than the rest of the world combined, but much of the energy has been wasted in ill-performing steel factories which rely on government subsidy for survival, according to the film.
Investigation into steel makers in Beijing's neighboring province of Hebei, exposed the conundrum between a GDP-driven economy and environmental protection.
Chai and Zhang Dawei, an investigator with the Ministry of Environmental Protection, recorded a steel company's illegal emission in Tangshan, a heavy industry center in October, only to find the company escaped punishment.
The former journalist goes on to disclose loopholes in car emission regulations, signifying the importance of the matter by quoting another number – 100 million, referring to new cars added to the road in China in the past 10 years.
Seeking a precedent, Chai traveled to London and Los Angeles, two cities considered role models in cleaning once hazardously polluted air.
Chai sums up by calling for individual responsibility in reporting illegal emitters via a hotline.
The documentary has provoked national discussion after going viral online, turning social media into a hot spot of conflicting views.
"Chai Jing's investigation into smog" remained one of the hottest hashtags on Sina Weibo, a Chinese version of Twitter, while the documentary has been viewed more than 17 million times on Youku, a major Chinese video sharing website.
Critics questioned the former anchor's motives, saying it remained uncertain whether a disease suffered by her young daughter was directly caused by smog in China with rumors circulating that she is a regular smoker, while praise also flooded into Weibo applauding Chai's efforts to inspire the public.
The film became so ubiquitous that Chen Jining, newly appointed minister of environmental protection, said he had called Chai to express his appreciation after watching the whole video.