In a dystopian nation, a public prosperity law like no other is in effect: The National Welfare Act, in which citizens between the ages of 18-24 are selected to die for their country. Twenty-four hours before a nanocapsule carries out their death, the chosen receive notifications called "Ikigami" from government messengers. The government gives only one ostensible reason for the act’s purpose—to spread the value of life.

Kengo Fujimoto is a newly instated Ikigami messenger who is indecisive on his stance of the act. Curbing his hesitation to avoid the watchful eye of the national police, Kengo decides that delivering the Ikigami will help shape his opinion.

Ikigami follows how people act knowing that their final hours are upon them. Whether committing acts of kindness or crimes of passion, the chosen's actions have profound impacts on those around them, and it will ultimately lead Kengo to his decision.

Ikigami was serialized in Young Sunday until its final issue on July 31, 2008. Serialization moved to Big Comic Spirits on September 15, 2008.

The series was published in English as Ikigami: The Ultimate Limit by VIZ Media under the VIZ Signature imprint from May 12, 2009 to August 19, 2014 and in Polish by Hanami from June 2010 to July 2013.

A live-action film was released on September 27, 2008.