Winter 1861. Sergeant Chesterfield, in charge of replacing Captain Stark, ended up finding his superior in the hospital for the same diagnosis: post-traumatic stress! The remedy: keeping him away from the war... General Alexander then asked him to accompany a certain Jeremiah Clure, geographer in charge of mapping the Indian territories. Little concern for Blutch and Chesterfield: Clure is anarchist. But worse: they must escort him to territories where the Southerners, allied to the Cherokees, persecute the Cree tribes, loyal to the Northernists...