There are many extraordinary things about the new documentary I Am Greta.
The first is that the film happened at all. Its director Nathan Grossman had never made a documentary feature before.
The former film student was curious when he heard, in 2018, that 15-year-old Swedish girl Greta Thunberg had decided to bunk off school to sit alone outside the country's parliament in Stockholm as part of what she was calling a "climate strike".
He started filming a few days later. At first he shot in a low-quality mode on his camera to save space on memory cards, thinking he would be lucky if her story made a short feature for the local news.
I Am Greta: The coming of age movie wrapped up in a super-hero flick
BBC News – Justin Rowlatt – 15th October 2020