In 1867, a time of turmoil for the Shinsengumi, Councilor Ito Kashitaro's complex espionage plan is put into action. Its ostensible purpose is to gain information on the Sat-Cho alliance, but as usual, Ito's got ulterior motives. When the selection of an outside member to join the Goryoeji espionage group causes controversy among the Shinsengumi rank and file, Sei, Okita, Saito, Hijikata, and Kondo reevaluate their roles in the organization.