Defying the norms of the sci-fi genre by exploring themes of race, power, gender and class, Octavia Butler's books feel totally modern.
The protagonist Dana, a strong, believable black woman, gets pulled back in time to save her ancestor who happens to be a white slave owner. As she lands back in 1815 she instantly loses all her rights as a human being as without papers her existence is illegal, so we feel firsthand the injustice and prejudice the author experienced as a black person and as a woman. This is a roller coaster of a read, the writing is so visual I can still picture scenes from it and Octavia Butler explores themes such as empathy, love as political resistance and adapting to change, making this is a must read.
See also Emergent Strategy by adrienne maree brown: radical self/society help inspired by the philosophies of Octavia Butler.