Historian Kerri Greenidge tells the story of William Monroe Trotter, a Black newspaper editor who was a forceful crusader for civil rights in the early 20th century. He built a national following in his time as a fierce advocate for the full citizenship rights that had been promised to former enslaved people after the Civil War. Trotter organized mass protests, confronted presidents, and openly challenged leaders such as Booker T. Washington who took a more cautious approach to Black empowerment. Greenidge's new book is called 'Black Radical.'Film critic Justin Chang reviews 'Promising Young Woman' and 'Pieces of a Woman.'