Blueback details the life of Abel Jackson, a diver and later marine biologist, from when he was 10 years old into his adult life. The title of the book originates from a fish Abel meets while diving in the bay near his house; a giant blue groper. Abel and his mother, Dora, name it Blueback, and they repeatedly visit it as it spends its life on the reef there. Abel lives with Blueback through many hard times, including protecting him from a poacher. Abel grows up to become a marine biologist as a result of his passion for the sea and love of Blueback.