Before Watchmen , Alan Moore made his debut in the U.S. comic book industry with the revitalization of the horror comic book The Swamp Thing . His deconstruction of the classic monster stretched the creative boundaries of the medium and became one of the most spectacular series in comic book history. With modern-day issues explored against a backdrop of horror, The Swamp Thing stories became commentaries on environmental, political and social issues, unflinching in their relevance. Saga of the Swamp Thing Book One collects issues #20-27 of this seminal series including the never-before-reprinted Saga of The Swamp Thing #20, where Moore takes over as writer and concludes the previous storyline. Book One begins with the story "The Anatomy Lesson," a haunting origin story that reshapes Swamp Thing mythology with terrifying revelations that begin a journey of discovery and adventure that will take him across the stars and beyond.