It's a feature-length selfie with a figure who merits a painstaking portrait.

Even more than describing her cause, the affecting "I Am Greta" introduces us to the person herself, digging deep into why she's pushing herself so hard, to do what our planet's adults apparently won't.

Grossman's fly-on-the-wall approach is a perfect match for his subject. Thunberg is not unselfconscious, but she has very little to prove, and so her single-minded passion for her activism comes through in every word she says.

aims to humanize the figure of young climate activist Greta Thunberg, but fails to paint a fair portrait.