While serving as the network liaison officer to National Commandant Rupied and Robert Esparre de Caen, she functioned as a courier under the alias "Jojo." Delivering resistance communications between Alençon, Caen, Paris, and Vire, she also observed and reported on the movement of German troops and equipment, and ultimately attained the rank of second lieutenant of the French Forces of the Interior, according to documents associated with the awards for valor which she would later receive from the French government. During the summer or fall of 1942, the Jeanne organization was infiltrated by a "mole," prompting its leaders to disband the network; their response came too late. Betrayed by that individual to the Geheime Staatspolizei (the Nazi Secret Police organization known more commonly as the "Gestapo"), multiple members of the former network were arrested in November 1942, including Robert Jeanne and Henri Brunet, who were captured on November 11, and Pierre Doucet, the Countess de Majo-Durezzo and Louis Esparre, who were found and arrested at Perpignan in December. Paulette Duhalde (aka "Jojo") also became one of those hunted during that roundup. Questioned by the Gestapo on December 9, 1942, while she was at work at the Banque de France branch in Flers, she managed to covertly transfer a bag of compromising Resistance documents to a co-worker, Mrs. Vaubaillon, while Gestapo officers were interviewing other bank employees. The Gestapo officers then resumed their questioning of her, made the decision to arrest her, and jailed her at the prison at Fresnes on December 12. Tried for espionage by a German Luftwaffe war council in Paris on May 11, she was sentenced on June 17, 1943 to five years of "fortress" imprisonment. Initially returned to the prison at Fresnes, she was housed on the third floor in cell number 308, and assigned to kitchen and prison cleaning details during which she swept floors and washed laundry. Moved to the prison at Aachen on July 8, 1943, she was then deported on July 22 to the Cottbus prison near Leipzig, Germany. On November 21, 1944, she was transported from Cottbus to the Ravensbrück concentration camp. A red triangle was affixed to her uniform, signifying her status as a political prisoner. Housed in overcrowded, unsanitary conditions where she was exposed to women suffering from a range of diseases, she became increasingly malnourished from the inadequate and poor quality of food provided.