For centuries, new sailors from European and North American countries have been subjected to an elaborate hazing at sea called “crossing the line.” Typically initiated upon a crossing of the equator, the beatings, dunkings, sexual play, and drinking displays that constitute crossing the line have in recent decades been banned by some fleets— but they have also been the subject of staunch defenses and fond reminiscences. Crossing the Line studies the purpose and the changing meaning of the ceremony, substantially revising long-held assumptions.