"In a world where disease has been eliminated, the only way to die is to be randomly killed ('gleaned') by professional reapers ('scythes'). Two teens must compete with each other to become a scythe--a position neither of them wants. The one who becomes a scythe must kill the one who doesn't"--

Rowan and Citra take opposite stances on the morality of the Scythedom, putting them at odds, and the Thunderhead is not pleased.