The Defence of the Realm (57 page)

The memoirs of Oscar Reile, BRUTUS's Abwehr recruiter, strongly suggest that Masterman's fears of the risks involved in running him as a double agent were fully justified. Reile claims to have realized that it was a ‘probability bordering on certainty' that BRUTUS (codenamed ARMAND by the Abwehr) was under British control: ‘Not the least of my reasons for arriving at this conclusion was that none of the radio messages which came from England contained any enquiry about the 66 members of the Reséau Interallié who were still in the hands of the Germans.'
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BRUTUS also became involved in a dispute in London with the head of the Polish air force which led to his court martial in the summer of 1943.
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As Reile complained, however, German military operations officers had no doubt that BRUTUS's reports contained important intelligence and dismissed his own suspicions of a British deception. BRUTUS's service background made it possible for B1a to include in his messages more military detail than would have been credible in GARBO's reports. Hugh Astor, who succeeded Harmer as his case officer in December 1943, wrote later:

Undoubtedly GARBO sent a far greater volume of traffic but the traffic sent by BRUTUS was much more professional in style and it was obvious from ULTRA that the Germans attached importance to his messages. Certainly I was under the impression that their projection of our order of battle was chiefly derived from BRUTUS.
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After reporting on (non-existent) preparations in Scotland for an attack on Norway, BRUTUS radioed the good news to the Abwehr on 26 May that he had been posted as a member of an Allied mission to the HQ of the (equally non-existent) First United States Army Group (FUSAG) at Wentworth, near Ascot, and had obtained its complete order of battle. TATE complemented and corroborated BRUTUS's battle-order intelligence by providing a schedule of FUSAG troop movements which he claimed to have acquired from a railway clerk in Ashford, Kent.
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The size of the non-existent FUSAG, whose reality was never doubted by the German high command, was greater than that of all the US forces which actually took part in the Normandy landings.
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The most recently recruited double agent to play an important part in the FORTITUDE deceptions was Nathalie ‘Lily' Sergueiev, a French Abwehr agent of White Russian origins who changed sides after being sent
on a mission to England in November 1943.
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Masterman wrote later that Sergueiev was ‘intelligent but temperamental' and eventually ‘proved exceptionally troublesome'.
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B1a's choice of TREASURE as her codename seems to have been deliberately satirical. As well as being one of the few female double agents of the war, TREASURE was the only one with a female case officer, Mary Sherer, who was not, however, allowed officer rank.
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Though the two women sometimes operated as an effective professional partnership, they never bonded. TREASURE later complained that her determination to undermine the Nazi war effort had been weakened by the unfeeling attitude of the British authorities to her and her dog Babs.
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From the moment she arrived in London, she was preoccupied with the treatment of Babs, whom she had left in Gibraltar in order to avoid having to subject her to six months in English quarantine kennels. TREASURE believed she had been given a promise that a way would be found, despite quarantine regulations, to bring Babs, to whom she was devoted, to join her in London. In December 1943 she refused to send more letters to the Abwehr until her dog arrived. Sherer, who does not seem to have been particularly sympathetic, reported that TREASURE was being ‘very unreasonable'.
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It is difficult to believe that the whole affair could not have been better handled.

TREASURE eventually suspended what Sherer called her ‘strike' after falling ill at the end of the year and spending a week in hospital. In March 1944 she flew to Lisbon to meet her Abwehr case officer and collect a radio transmitter
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– a fact of sufficient importance to be reported to Churchill.
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While in Lisbon she was also given money and codes for her mission in England, presented with souvenir photographs of herself and her case officer, and rewarded with a diamond bracelet.
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After returning to London TREASURE reported to the Abwehr by radio that, during regular weekend visits to Bristol, she had seen very few troop movements in south-west England,
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thus reinforcing the German belief that the main Allied troop concentrations were in the south-east, preparing for an invasion of the Pas de Calais. (In reality, in preparation for D-Day, most Allied forces were in the south-west.) The Abwehr attached great importance to TREASURE's reports. Bletchley Park reported in May that ‘The messages of TREASURE and BRUTUS are being so consistently relayed verbatim on the German Intelligence W/T [wireless telegraphy] network that, with the assistance of this “crib”, there has been a very considerable saving of time and manpower in deciphering Most Secret [SIGINT] Sources.' This, the Security Service told Churchill, was proof that the double agents ‘have, at a critical period, acquired a value which it is scarcely possible to overestimate'.
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The code given to TREASURE by her Abwehr case officer.

Coded radio message from TREASURE to her Abwehr case officer falsely reporting her arrival in Bristol in November 1943.

Churchill was also given evidence of how much German intelligence valued the disinformation sent them by TRICYCLE and TATE. Pride of place in the double-agents section of MI5's April monthly report to the Prime Minister went to TRICYCLE, just returned from visiting ‘his German masters' in Lisbon: ‘He has once more succeeded in convincing them of his complete reliability and has extracted from them a large sum in dollars as an advance against his future services.'
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Churchill was told that, when TATE transmitted his thousandth radio message to the Abwehr on 24 May:

He took the opportunity of referring to this fact and expressing his loyal devotion to the Führer. A cordial reply has been received, and it is hoped that this will be followed up by the further advancement of TATE in the Order of the Iron Cross, of which he already holds the First and Second Class.
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During the month before D-Day, however, the Double-Cross System suffered two near-disasters. The first derived from the death in Portugal of TREASURE's much loved dog Babs, for which she blamed the uncaring British. On 17 May TREASURE startled her case officer, Mary Sherer, by admitting that she had planned a terrible revenge. While in Lisbon she had obtained from her Abwehr case officer a ‘control signal' to add to her transmissions; if she omitted it, that would be a sign that the British had taken over her transmitter:

She had meant, on her return, to get the W/T working well and then blow the case by omitting the signal. She confessed that her motive was revenge for the death of her dog for which she considered we were responsible. On return from Lisbon she had changed her mind about blowing the case. She refused to divulge what the signal was.
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Tar Robertson was thus faced, less than three weeks before D-Day, with an appalling dilemma: either to arouse German suspicions by abruptly ending TREASURE's transmissions or to allow her to continue in the hope, but without the certainty, that she really had ‘changed her mind about blowing the case'. Probably after consultation with Masterman, Robertson chose the second option.
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An even greater threat to the Double-Cross System arose from the arrest by the Gestapo in early May of TRICYCLE's Abwehr case officer in Lisbon, ARTIST, who had himself become a double agent.
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Before his arrest ARTIST had made clear to his British case officer that he knew TRICYCLE and GARBO were double agents,
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and it was thought likely that he suspected other German agents in Britain had also been turned.
Only three days before D-Day Churchill was warned by the Security Service that ‘the TRICYCLE case is passing through a most critical phase and must be handled with the greatest care in view of Overlord'.
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ARTIST was believed to have been arrested for embezzlement rather than because the Gestapo suspected him of being a British agent. But, as Masterman wrote later:

That belief was small consolation. Under interrogation it was to be presumed that much, if not all, of the history of [ARTIST's] activities would come to light, and in that case many of our best cases were doomed.

… We were saved by time and fortune. D Day arrived before the Germans had succeeded in unravelling all the tangled skein of the ARTIST case, and presumably there was little opportunity after D Day for patient research into such matters in German offices.
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On 1 June Bletchley Park produced reassuring evidence that, despite the potential threats posed by ARTIST and TREASURE, the key elements of the strategic deception on which the D-Day landings depended were still intact. A Japanese decrypt revealed that Hitler had told the Japanese ambassador, Baron Hiroshi Oshima, that eighty enemy divisions had been assembled in Britain for the invasion. In reality there were only forty-seven, but the Führer, like his high command, had been deceived into believing in the non-existent FUSAG as well as misled about where the main Allied attack would come. Hitler told Oshima that after ‘diversionary attacks . . . in a number of places', the Allies would then use their main forces for ‘an all-out second front across the Straits of Dover'.
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The final act in the pre-D-Day deception was entrusted, appropriately, to its greatest practitioners, GARBO and Tomás Harris. After several weeks of pressure, Harris finally gained permission for GARBO to be allowed to radio a warning that Allied forces were heading towards the Normandy beaches just too late for the Germans to benefit from it. Though the Abwehr radio station in Madrid normally shut down from 11.30 p.m. to 7.30 a.m., GARBO warned it to be ready to receive a message at 3 a.m. on 6 June (D-Day).
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But, for unknown reasons, Madrid did not go on air until after 6 a.m., and received the warning several hours later than intended.
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