Very good adaption of the book with truly excellent acting!
Many commentors have complained that their main problem with the movie is that they don't believe that Tessa Thompson and Ruth Negga could pass for white. I would argue that this is likely because we all know that these actresses are black, if you did not know who Ruth Negga was and saw her for the first time as her character Claire sitting in the restaurant you would probably assume she was white. As for Irene (Tessa Thompson's character) she only tries to pass for white in certain situations like when she goes into a nice restaurant, and she keeps her hat pulled down closely over her face and is nervous about being caught.
Also, back in the 1920s most white people had a specific idea of what black people looked like, whereas today most white people know that black people have various skin tones. In the 1934 film "Imitation of Life", the great black actress Fredi Washington played a character who passes for white. Today (in 2021) most people would immediately recognize Ms. Washington as black, but back in the 1920s and 30s people didn't associate fair skin and green eyes with the black race.
Most importantly, the film is told from a black perspective, and "passing" was about fooling white people, not fooling other black people, so the fact that the audience knows and sees them as black helps the movie.
As for the acting, both of these actresses are truly amazing, especially Ruth Negga who I think will earn another Oscar nomination. Wonderful, moving dialog and musical score. I highly recommend!