Jeff Lindsay published eight Dexter novels from 2004 to 2015. The sequence begins with Darkly Dreaming Dexter and ends with Dexter Is Dead, the eighth and final novel in the main book series.
The books were released over eleven years: Darkly Dreaming Dexter in 2004, followed by Dearly Devoted Dexter, Dexter in the Dark, Dexter by Design, Dexter Is Delicious, Double Dexter, Dexter’s Final Cut, and Dexter Is Dead. The novels follow Dexter Morgan’s private life and his activities as a killer who targets other criminals.
The count can be confusing because the television franchise has produced multiple series, web projects, comics, and other tie-in material. Those should not be added to Lindsay’s eight main novels. Graphic novels and television episodes are separate works, not additional Jeff Lindsay novels.
The TV adaptation also diverges sharply from the books after its first season. Although the original show used Darkly Dreaming Dexter as a major source, its later storylines do not correspond one-for-one with the remaining seven novels.