"Ice" is a science fiction anime series set in a dystopian future where humanity faces extinction due to a mysterious virus known as the "ICE Virus." The virus causes individuals to crystallize and shatter, leading to widespread panic and societal collapse. The story centers on a group of genetically engineered individuals called the "ICE Children," who are immune to the virus and possess unique abilities. These children are raised in isolation by a secretive organization known as the "ICE Foundation," which aims to use them to combat the virus and restore order.

The protagonist, Aoi, is one of the ICE Children, distinguished by her exceptional combat skills and leadership qualities. Alongside her fellow ICE Children, including the analytical Kazuya and the empathetic Satoshi, Aoi is tasked with venturing into the infected zones to gather data and eliminate threats. As the series progresses, the group uncovers unsettling truths about the origins of the ICE Virus and the true intentions of the ICE Foundation. They learn that the virus was not a natural occurrence but a man-made weapon designed to control population growth, and the ICE Children were created as tools to enforce this agenda.

The narrative explores themes of identity, free will, and the ethical implications of genetic engineering. The ICE Children grapple with their purpose and the morality of their actions, questioning whether they are saviors or pawns in a larger scheme. Their journey is fraught with internal and external conflicts, as they face off against rogue factions, mutated creatures, and their own doubts. The series culminates in a climactic confrontation between the ICE Children and the ICE Foundation, forcing them to make difficult choices about their future and the fate of humanity. The story concludes with an open-ended resolution, leaving room for interpretation regarding the ultimate outcome of their struggle.