Enigma

still too much in awe of Turing not to do as he was told. He tugged his jacket off the back of his chair and walked out, shrugging it on, into the May sunshine.
    By this time the Park had already started to be transformed. Most of the trees at the side of the lake had been chopped down to make way for a series of large wooden huts. The maze had been uprooted and replaced by a low brick building, outside which a small crowd of cryptanalysts had gathered. There was a sound coming from within it, of a sort Jericho had never heard before, a humming and a clattering, something between a loom and a printing press. He followed Turing through the door. Inside, the noise was deafening, reverberating off the whitewashed walls and the corrugated iron ceiling. A brigadier, an air commodore, two men in overalls and a frightened-looking Wren with her fingers in her ears were standing round the edge of the room staring at a large machine full of revolving drums. A blue flash of electricity arced across the top. There was a fizz and a crackle, a smell of hot oil and overheated metal.
    'It's the redesigned Polish bombe,' said Turing. 'I thought I'd call her Agnes.' He rested his long, pale fingers tenderly on the metal frame. There was a bang and he snatched them away again. 'I do hope she works all right
    Oh yes, thought Jericho, rubbing another window into the condensation, oh yes, she worked all right.
    The moon slid from beneath a cloud, briefly lighting the Great North Road. He closed his eyes.
    She worked all right, and after that the world was different.
    Despite his earlier wakefulness Jericho must have fallen asleep, for when he next opened his eyes Logie was sitting up and the Rover was passing through a small town. It was still dark and at first he couldn't get his bearings. But then they passed a row of shops, and when the headlights flickered briefly on the billboard of the County Cinema (NOW SHOWING: 'THE NAVY COMES THROUGH', 'SOMEWHERE I'LL FIND YOU'), he muttered to himself, and heard the weariness already creeping back into his voice: 'Bletchley.'
    'Too bloody right,' said Logie.
    Down Victoria Road, past the council offices, past a school . . . The road curved and suddenly, in the distance, above the pavements, a myriad of fireflies were swarming towards them. Jericho passed his hands across his face and found that his fingers were numb. He felt mildly sick.
    'What time is it?'
    'Midnight,' said Logie. 'Shift change.'
    The specks of light were blackout torches.
    Jericho guessed the Park's workforce must now be about five or six thousand, toiling round the clock in eight-hour shifts—midnight till eight, eight till four, four till midnight. That meant maybe four thousand people were now on the move, half coming off shift, half going on, and by the time the Rover had turned into the road leading to the main gate it was barely possible to advance a yard without hitting someone. Leveret was alternately leaning out of the window, shouting and hammering on the horn. Crowds of people had spilled out into the road, most on foot, some on bicycles. A convoy of buses was struggling to get past. Jericho thought: the odds are two to one that Claire's among them. He had a sudden desire to shrink down in his seat, to cover his head, to get away.
    Logie was looking at him curiously. 'Are you sure you're up to this, old thing?'
    I'm fine. It's just—it's hard to think it started with sixteen of us.'
    'Wonderful, isn't it? And it'll be twice the size next year.' The pride in Logie's voice abruptly gave way to alarm. 'For God's sake, Leveret, look out man, you nearly ran that lady over!'
    In the headlights a blonde head spun angrily and Jericho felt a rush of nausea. But it wasn't her. It was a woman he didn't recognise, a woman in an army uniform, a slash of scarlet lipstick like a wound across her face. She looked as if she was tarted up and on her way to meet a man. She shook her fist and mouthed 'Bugger off at them.
    'Well,' said Logie, primly, 'I thought she was a lady.'
    When they reached the guard post they had to dig out their identity cards. Leveret collected them and passed them on through the window to an RAF corporal. The sentry hitched his rifle and studied the cards by torchlight, then ducked down and directed the beam in turn on to each of their faces. The brilliance struck Jericho like a blow. Behind them he could hear a second sentry rummaging through the boot.
    He flinched from the light and turned to Logie. 'When