Editing Juan Pujol García (section)

=== Work with MI5 ===
The British had become aware that someone had been misinforming the Germans, and realised the value of this after the {{lang|de|[[Kriegsmarine]]}} wasted resources attempting to hunt down a non-existent convoy reported to them by Pujol.<ref name=elespia/> He was moved to Britain on 24 April 1942 and given the code name "Bovril", after [[Bovril|the drink concentrate]]. However, after he passed the security check conducted by [[MI6]] Officer [[Desmond Bristow]], [[Desmond Bristow|Bristow]] suggested that he be accompanied by MI5 officer [[Tomás Harris]] (a fluent Spanish speaker) to brief Pujol on how he and Harris should work together. Pujol's wife and child were later moved to Britain.<ref name=MarkSeaman30/>

Pujol operated as a [[double agent]] under the [[Double Cross System|XX Committee]]'s aegis. Cyril Mills was initially Pujol's case officer, but he spoke no Spanish and quickly dropped out of the picture. Mills suggested that Pujol's code name should be changed as befitted "the best actor in the world", and Pujol became "Garbo", after [[Greta Garbo]].<ref name=TheDeceiversHolt>[[#Holt|Holt (2010)]]. [https://books.google.com/books?id=E569Q7s1CnsC&lpg=PA846 p. 210]. "Mills was initially BOVRIL's case officer; but he spoke no Spanish and quickly dropped out of the picture. His main contribution was to suggest, after the truly extraordinary dimensions of Pujol's imagination and accomplishments had become apparent, that his code name should be changed as befitted 'the best actor in the world'; and BOVRIL became GARBO."</ref> Mills passed his case over to the Spanish-speaking officer Harris.<ref name=MI5 /> Together, Harris and Pujol wrote 315 letters, averaging 2,000 words, addressed to a post-office box in Lisbon supplied by the Germans. His fictitious spy network was so efficient and verbose that his German [[Handler (spying)|handlers]] were overwhelmed and made no further attempts to recruit any additional spies in the UK, according to the ''Official History of British Intelligence in World War II''.<ref name=MI5/>

[[File:MI5 Case Officer Tomás (Tommy) Harris 1942.jpg|thumb|upright=1.2|Pujol's case officer at MI5, [[Tomás Harris]]]]

The information supplied to German intelligence was a mixture of complete fiction, genuine information of little military value, and valuable military intelligence artificially delayed. In November 1942, just before the [[Operation Torch]] landings in [[North Africa]], Garbo's agent on the [[River Clyde]] reported that a convoy of troopships and warships had left port, painted in Mediterranean camouflage. While the letter was sent by airmail and postmarked before the landings, it was deliberately delayed by British Intelligence in order to arrive too late to be useful. Pujol received a reply stating "we are sorry they arrived too late but your last reports were magnificent."<ref name=MI5/>

Pujol had been supposedly communicating with the Germans via a courier, a [[KLM|Royal Dutch Airlines]] (KLM) pilot willing to carry messages to and from Lisbon for cash. This meant that message deliveries were limited to the KLM flight schedule. In 1943, responding to German requests for speedier communication, Pujol and Harris created a fictitious radio operator. From August 1943 radio became the preferred method of communication.<ref name=MI5/><ref name=Holt213>[[#Holt|Holt (2010)]]. [https://books.google.com/books?id=E569Q7s1CnsC&pg=PA213 p. 213].</ref>

On occasion, he had to invent reasons why his agents had failed to report easily available information that the Germans would eventually know about. For example, he reported that his (fabricated) Liverpool agent had fallen ill just before a major fleet movement from that port, and so was unable to report the event.<ref name=MarkSeaman96>[[#Seaman|Seaman (2004)]]. [https://books.google.com/books?id=Ut5y5vwKyW4C&pg=PA96 p. 96].</ref> To support this story, the agent eventually "died" and an [[obituary]] was placed in the local newspaper as further evidence to convince the Germans.<ref name=MarkSeaman106>[[#Seaman|Seaman (2004)]]. [https://books.google.com/books?id=Ut5y5vwKyW4C&pg=PA106 p. 106].</ref> The Germans were also persuaded to pay a pension to the agent's "widow".<ref name=MarkSeaman126>[[#Seaman|Seaman (2004)]]. [https://books.google.com/books?id=Ut5y5vwKyW4C&pg=PA126 p. 126].</ref>

For radio communication, "Alaric" needed the strongest hand encryption the Germans had. The Germans provided Garbo with this system, which was in turn supplied to the codebreakers at [[Bletchley Park]]. Garbo's encrypted messages were to be received in Madrid, manually decrypted, and re-encrypted with an [[Enigma machine]] for retransmission to Berlin.<ref name=BBC_News_Magazine>{{cite news|last=Kelly|first=Jon|title=The piece of paper that fooled Hitler|url=https://www.bbc.co.uk/news/magazine-12266109|publisher=BBC|access-date=1 January 2012|quote=The Nazis believed Pujol, whom they code named Arabel, was one of their prize assets|date=27 January 2011|archive-date=19 January 2012|archive-url=https://web.archive.org/web/20120119013350/http://www.bbc.co.uk/news/magazine-12266109|url-status=live}}</ref> Having both the [[plaintext|original text]] and the Enigma-encoded intercept of it, the codebreakers had the best possible source material for a [[chosen-plaintext attack]] on the Germans' Enigma key.<ref name=MarkSeaman73>[[#Seaman|Seaman (2004)]]. "The first code which Garbo was given by the Germans for his wireless communications turned out to be the identical code which was currently in use in the German circuits."</ref>