The work runs to 108 chapters in the Ethiopic text, and scholars divide it into five compositions of different date and different concerns, joined because all of them speak in the voice of Enoch.
Chapters 1 to 36 are the Book of the Watchers. Two hundred angels descend, take human wives, and father the giants of Genesis 6; their leaders are Shemihazah, who organises the oath and the descent, and Azazel, who teaches metalwork, weapons, and the cosmetics of seduction. The giants devour the earth, the archangels bring the cry of the dead before God, and Enoch is sent to the Watchers with a judgement they cannot appeal. Chapters 17 to 36 send him on a tour of the ends of the earth, the places of punishment and the chambers of the dead.
Chapters 37 to 71 are the Book of Parables, or Similitudes, three visions dominated by a heavenly figure called variously the Chosen One, the Righteous One, the Anointed One and that Son of Man, who sits on a throne of glory to judge kings.
Chapters 72 to 82 are the Astronomical Book, a technical account of the movements of sun and moon, the gates of the winds, and a year of 364 days. Chapters 83 to 90 are the Book of Dreams, containing the Animal Apocalypse, which retells Israel's history with the nations as animals and the patriarchs as bulls and sheep. Chapters 91 to 108 are the Epistle of Enoch, including the Apocalypse of Weeks, which divides all history into ten weeks with the writer's own generation near the end. The moral temperature of the Epistle is different again: sustained, furious address to the rich.