As Britain's most important double agent of World War 2, the brilliant and cunning Juan Pujol Garcia - code named "Garbo" by MI5 - proved crucial in defeating Nazi Germany. However, during his pivotal work in giving the Germans a false location for the Allies' D-Day landings on June 6 1944 he came terrifyingly close to having his cover blown by his wife.MI5 files recently released by the National Archives in Britain show that his scheming was nearly wrecked because his spouse, Araceli, struggled to cope with the pressures of his double life.Araceli, from Spain, complained of homesickness as she failed to settle into life in the London suburb of Harrow where Garbo ran a network of fictitious sub-agents whom he credited with generating the false intelligence reports he sent back to his German spy masters.She even threatened to expose Garbo as he worked to convince the Nazis that the D-Day landings would be at the Pas de Calais - diverting German forces away from Normandy, scene of the actual invasion, saving countless Allied lives.Fears that the deception would unravel if she were recognised by fellow Spaniards in London necessitated her movements being strictly controlled by Pujol and she was largely confined to the house with her two children, to her intense frustration.BLUFFED: Araceli Garcia, wife of double agent Juan Pujol Garcia Picture: PA/NATIONAL ARCHIVES MASTER OF DECEPTION: Juan Pujol Garcia fooled the Nazis and his wife Picture: PA/NATIONAL ARCHIVES Matters came to a head in June 1943 - a year before D-Day - when, after quarrelling violently with her husband, Araceli Pujol threatened to go to the Spanish embassy and tell all unless she was allowed to travel home to see her mother."I don't want to live five minutes longer with my husband," she screamed at Pujol's MI5 case officer, Tomas Harris."Even if they kill me I am going to the Spanish embassy."With a visit to Spain out of the question, Harris suggested she should be told Pujol had been sacked as a result of her outburst, while quietly allowing him to carry on his work against the Germans under the cover of working as a BBC translator.However, Pujol felt more drastic action was needed. With the agreement of MI5 he came up with a deception plan every bit as cunning as those he used to fool the Germans.The next day, Araceli Pujol was told that her husband had been detained following an argument with his MI5 spy masters over her treatment. She then threatened to take the children and "make a disappearance".An MI5 officer sent to check up on her found she had turned on all the gas taps in the house in what was taken to be a suicide attempt.The following afternoon, a tearful Araceli Pujol was taken blindfolded to MI5's Camp 020 interrogation centre in west London, where her husband was brought before her, unshaven and dressed in camp clothing.In an emotional reunion, she swore to him she had never meant to carry out her threat to go to the embassy and had simply wanted her request to return home to be taken seriously."She promised that if only he were released from prison she would help him in every way to continue his work with even greater zeal," Harris noted.The charade was not quite over, however.Araceli Pujol was then taken before MI5's legal adviser, Major Edward Cussen, who, after giving her a stern dressing down, told her he had decided her husband should be released and allowed to continue his work."He reminded her that he had no time to waste with tiresome people and that if her name was ever mentioned to him again he would simply direct that she be locked up," Harris said."She returned home very chastened to await her husband's arrival." - ©The Daily Telegraph..