Saichi Sugimoto, also known as the "Immortal Sugimoto," gained a reputation for his ruthless actions during the Russo-Japanese war, though he hardly deserves to be called a hero. Discharged from the army after he assaulted a higher-ranking officer, Sugimoto must now survive the unforgiving terrain of Hokkaido. Despite tirelessly searching for gold in honor of his fallen comrade, he finds no success until a mysterious traveler tells him of an urban legend.
The legend speaks of a thief who stole gold from the Ainu people - natives of Hokkaido - and hid it in a secret location, marked only by a map made of tattoos from escaped prisoners. When Sugimoto meets a young Ainu girl named Asirpa, they team up to embark on a treacherous journey to find the prisoners and their treasure. But other treasure hunters, including soldiers and mercenaries, are also on the hunt for the Ainu gold, making their quest a dangerous one filled with violence and greed. Asirpa brings knowledge of the land, while Sugimoto brings the desire for revenge and riches. Together, they plunge headfirst into a perilous adventure.