The Deep tells a story of a race of mer-creatures, wajinru, evolved from the pregnant African slave women thrown overboard during the slave trade. If that isn't a difficult story to read in and of itself, I don't know what is. The story (mostly) follows Yetu, a historian, the wajinru tasked with holding the entire history of their people, so that the others don't have to bear the weight of it. However, Yetu doesn't want the responsibility of historian any more, so she escapes. Aside from the story, another reason this was difficult to read was that the prose was so dense that I struggled to get through the first half of this book. I was, however, most interested in the relationship between Yetu and Oori, and I wish that had been fleshed out a bit more. I wasn't so much interested in the story of the others before Yetu and could have done without those stories. I would have read this whole book about Yetu and Oori.