Enigma

reached over and picked up one of Jericho's discarded mystery stories, flicked through it, smiled, replaced it.
    'You know, Tom,' he said thoughtfully, 'there's never been anything like Bletchley Park in the history of the world. There's never been a time when one side knew so much about its enemy. In fact, sometimes, I think, it's possible to know too much. When Coventry was bombed, remember? Our beloved Prime Minister discovered from Enigma what was going to happen about four hours in advance. Know what he did?
    Again Jericho shook his head.
    'Told his staff that London was about to be attacked and that they should go down to the shelters, but that he was going upstairs to watch. Then he went out on to the Air Ministry roof and spent an hour waiting in the freezing cold for a raid he knew was going to happen somewhere else. Doing his bit, d'you see? To protect the Enigma secret. Or, another example: take the U-boat tankers. Thanks to Shark, we know where they're going to be, and when, and if we knocked them out we might save hundreds of Allied lives—in the short term. But we'd jeopardise Enigma, because if we did that, Donitz would know we must be reading his codes. You see what I'm driving at? So Stalin has killed ten thousand Poles? I mean, please, Uncle Joe's a national hero. He's winning the frigging war for us. Third most popular man in the country, after Churchill and the King. What's that Hebrew proverb? “My enemy's enemy is my friend”? Well, Stalin's the biggest enemy Hitler's got, so as far as we're concerned, for present purposes, he's a bloody good friend of ours. Katyn massacre? Katyn frigging massacre? Thanks awfully, but, really, do shut up.'
    'I don't suppose Puck would have seen it quite like that.'
    'No, old chap, I don't suppose he would. Shall I tell you something? I think he rather hated us. After all, if it hadn't been for the Poles, we might not even have broken Enigma in the first place. But the people he really hated were the Russians. And he was prepared to do anything to get revenge. Even if it meant helping the Germans.'
    '“My enemy's enemy is my friend,”' murmured Jericho, but Wigram wasn't listening.
    'And how could he help the Germans? By warning them Enigma wasn't safe. And how could he do that? Wigram smiled and spread his hands. 'Why, with the assistance of his old friend from 1940, Rogerio Raposo, recently transferred from Lisbon and now employed as a courier at the Portuguese legation in London. How about some tea?
    For the dear ones parted from us
    We would raise our hymns of prayer;
    By the tender love which watcheth
    Round thy children everywhere ...
    Senhor Raposo, said Wigram, sipping his tea after the nurse had gone, Senhor Raposo, presently a resident of His Majesty's Prison, Wandsworth, had confessed to everything.
    On 6 March, Pukowski had gone to see Raposo in London, handed him a thin, sealed envelope and told him he could make a great deal of money if he delivered it to the right people.
    The following day, Raposo flew on the scheduled British Imperial Airways flight to Lisbon carrying said envelope, which he passed to a contact of his on the staff of the German naval attache".
    Two days after that, the U-boat service changed its Short Weather Code Book, and a general review of cipher security began—Luftwaffe, Afrika Korps . . . Oh, the Germans were interested, of course they were. But they weren't about to abandon what their experts still insisted was the most secure enciphering system ever devised. Not on the basis of one letter. They suspected a trick. They wanted proof. They wanted this mysterious informant in Berlin, in person.
    'That's our best guess, anyway.'
    On 14 March, two days before the start of the; convoy battle, Raposo made his next weekly trip to-Lisbon and returned with specific instructions for Pukowski. A U-boat would be waiting to pick him up; off the coast of northwest Ireland on the night of the 18th.
    'And that was what they were discussing on the train,' said Jericho.
    'And that was what they were discussing on the; train. Quite right. Our man Puck was collecting his; ticket, so to speak. And shall I tell you the really frightening thing?' Wigram took another sip of tea, his little finger delicately crooked, and looked at Jericho over the rim of his cup. 'If it hadn't been for you, he might just have got away with it.'
    'But Claire would never have gone along with this,'; protested Jericho. 'Passed on a few intercepts—yes. For? a