An epic poem recounts the rebellion of a high angel who leads a host against Heaven, their fall and punishment, the plotting of the fallen to corrupt humankind; it then traces the creation of the first human couple, their temptation by the tempter, their disobedience and consequent loss of paradise, and the divine plan for human redemption. The poem explores themes of free will, authority, obedience, and theodicy, presents cosmic battles and debates among celestial beings, and balances grand rhetoric with intimate scenes between the couple; its twelve-book structure moves between Heaven, Hell, and Eden to examine cause, consequence, and mercy.