Nothing on the cover led me to understand this was a sequel to another book, so I was a good chunk into the book before I entered it on this site. It doesn't seem to be lacking a predecessor - stands on its own alright. And it's a fine book as it is. 
 I'm guessing it works for me better now that I see parallels of authoritarianism and bigotry shaking up our country. So if you're wondering if Donald Trump has accomplished anything yet, he's made an old Octavia Butler book way more relevant that it ought to be.