Who is "M" (The Property of a Lady), (The Living Daylights) from Octopussy and what is their importance?

Maria Freudenstein is a junior clerk in the Communications Section at the Secret Service Headquarters. She is also a known KGB double agent who is being fed misinformation for transmission to Moscow. This operation "Purple Cipher" has been going on for three years. Maria was born in Paris in 1935 and helped her mother run the Tulip Escape Route during the war.