Mathilde Carré was born in France. In the 1930's she attended Sorbonne University and became a teacher. After her marriage, she moved to Algeria with her husband.
Carre's husband was killed at the early stages of the World War Two. She returned to France, became a nurse and witnessed the fall of France. In 1940 she met a Polish officer Roman Cherniawski. Carre joined his Interallie espionage network and took a code name Chatte, the Cat. She reported information she had gleaned from the conversations of German officers.
In November 17 1941 Abwehr group of Hugo Bleicher arrested Carre and many other members of the Interallie; they had been betrayed by a double agent. She was threatened with torture and agreed to become a double agent herself, still representing Interallie. She also revealed most of the members of the network. She began to work for Germans with the old code name Victoire. Some commentators believe he may have also ended up as Bleicher's mistress.
Pierre de Vomécourt, Resistance contact begun to suspect her. When she confronted Carre, she confessed. Briefly she played a triple role.
According to herself, she convinced Bleicher to send her to London to infiltrate the Special Operations Executive. In February 1942 she went to London with de Vomécourt. MI5 interrogated her about Abwehr techniques and she was arrested as a spy. She was taken to a Holloway prison for the rest of the war.
After the war Carre was deported to France. Despite of the fact that her wartime commander Paul Archard defended her, she was sentenced to death. After couple of months the sentence was commuted to life imprisonment.
Mathilde Carre was released September 1954. She published an account of her life in "J'ai été la Chatte" but soon fell out of public view. She died in 1970.