In the 17th century, Europe is going through a difficult time due to the Thirty Years War. Despite sending reinforcements to The Holy Roman Empire, most of them deserted except for one person - a Japanese man named Issak. He traveled from East Asia in search of the murderer of his master and someone who took something valuable to him. Believing that the killer had joined one of the opposing armies, Issak decided to participate in the war as a mercenary with the hope of finding and ending his rivalry once and for all.
Issak has been published digitally in English by Kodansha USA since August 15, 2023.