The documentary is narrated by Chai, who presents the results of her year-long research mostly in the form of a lecture, reminiscent of Al Gore's "An Inconvenient Truth". The Great Smog of 1952 in London served as historical evidence Chai in creating her film. She reveals footage and data from factory visits and interviews with government officials, environmental experts and business owners. She also speaks with officials from London and Los Angeles on how their respective cities have managed to deal with historic issues of pollution. She says she has a personal grudge against smog, and sets out to answer three questions: What is smog? Where does it come from? And what can we do about it? For the rest of this 104 min-long ‘Ted Talk-style’ film, she answers these questions, using animations, charts, interviews, historical clips, and site visits.