Secret War in Portugal [1939-1945]
For SOE [British Special Operation Executive] 24 Land was the code name for Portugal

Marguerite (Rita) Winsor

[After my sources]

Marguerite (Rita) Winsor [not Windsor] worked in Bletchley Park, with the codebreakers, later in the forties in Lisbon, at the British Embassy, posing as typist, accordingly with the official list of personnel transmitted to the Portuguese Foreign Office.
She was an agent of MI6 as a Secretary. She provided visas for Ian Fleming, Somerseth Maugham and Malcolm Muggeridge, all from the Secret Service; and Alexander Korda, film director
In Otto John escape to Portugal, after failed attempt to kill Adolph Hitler, she had a relevant role in exfiltrating him. John describe it with fulll detail in his book of memoirs.
She was a friend of Klop Ustinov, also an MI6 agent.
After the war she established a travel agency [see The Times, 6 May 1957]. Nadia Benois, Klop's wife designed a poster for the wall of the bureau
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I am conducting a research about her role in the Secret Service during the war. After a close friend of her, she had a house in Algarve (Vila Nova de Cacela, Casa Marguerite, n.º 4). She died there, and funeral was in Sufolfk (UK).

Desmond Bristow letter


Desmond Arthur Bristow [Mi6 agent in Spain] wrote me this letter, dated 24.09.1998. I found his book A Game of Moles, signed, at Foyles. Strange event. He told me he was never there autographing books. Mistery surrounding spies...

Kenneth Benton

Born in Wolverhampton (UK) in 1909, recruited to Mi6 in 1937; working on PCO in Vienna, later in Riga (Latvia, acting as Vice-Consul, from 1938 till 1940 (occupation of the Baltic States by USSR). 
From 1941 to 1944 served in Madrid as head of counter espionage [Section V of Mi6, posing as 3d Secretary].  There he reported technically to Hamilton Stokes, Head of the Madrid SIS Station].
He was alowed to read ISOS traffic.
After his work, Treasure, Artist, Tricycle and Garbo were sent to England to work with XX Committee. 
Having worked under "Kim" Philby direction, the defection of this one to Moscow has "blown" his cover. He continued to serve Mi6 in Rome [1944-1948, 2nd and later 1st Secretary, 1950-1953], Spain (1953-1956), Peru and Brazil.
Married to Peggien Pollock Lambert.
Retired in 1968. Died in 1999.
He wrote twelve fiction books and was President of the Crime Writers Association.
Twenty-fourth Level1969WM Collins
Sole Agent1970WM Collins
Spy in Chancery1972WM Collins
Craig and the Jaguar1973Macmillan
Craig and the Tunisian Tangle1974Macmillan
Death on the Appian Way1974Chatto & Windus
Craig and the Midas Touch1975Macmillan
The Red Hen Conspiracy1982Macmillan
A Single Monstrous Act1982Macmillan
Time for Murder1985Robert Hale
Ward of Caesar1985Robert Hale
Greek Fire1985Robert Hale
 I wrote about him here.