Gabimaru the Hollow, a ninja facing execution, feels indifferent towards his death after a life drenched in violence. Surprisingly, all efforts to execute him have failed. When Yamada Asaemon Sagiri, a young member of a renowned executioner family, is tasked with ending his life, she refrains from doing so, suggesting instead that Gabimaru’s unyielding will to live stems from his deep love for his wife.
Sagiri proposes that Gabimaru can earn a full pardon by retrieving the Elixir of Life from the mystical island of Shinsekyo for the shogun—a potion said to bestow eternal life. Despite the ominous history of the island, where no explorer has returned sane or at all, Gabimaru agrees to undertake the perilous journey. Alongside ten other death row prisoners, he embarks on this daunting quest, driven by the hope of reuniting with his wife and leading a peaceful life.
[Adapted from MAL]