Hulu's 'I Am Greta' is a stirring but familiar portrait of a young activist

Greta Thunberg has never been one to mince words. She's never been shy about what she stands for, or what she'll do to fight for it. She's stood on the biggest platforms in the world to plead for change, or shame leaders who've failed to deliver it. Though she's sure to have her secrets, like any other human on the planet, she's...