'And then,' Josef said, 'the possibilities are unlimited.'

Ernst said, 'You always were an ambitious bastard, Josef. You plan to sell this fantasy of a time manipulator to Himmler, do you?'

'Well, you know he would be receptive. The Reichsfuhrer dreams of super-weapons. A plane that could strike at America. The Hammer of Thor! What would he make of the greatest weapon of all? For what enemy could stand before us, if his very past could be cut away?'

Ernst shook his head. 'You're mad. It's as simple as that.'

Josef sighed. 'How disappointing you are, brother, as you have always been. And yet I love you even so. And that is why I want you to share my great adventure, even if you are incapable of understanding it – '

A siren wailed mournfully.

'Ah,' Josef said. 'It sounds as if the RAF is coming to join the party. What a pity.' He drained his cognac, stood, and bowed to Claudine. 'Mademoiselle. Don't be too rough with my little brother; he does break easily, you know.' He glanced down at the ruined tabletop, brushed some splinters from it, and, with Julia, walked away.

Claudine touched Ernst's hand. 'You shouldn't let him upset you. It's what he wants.'

'He's had a lifetime's practice at it.'

She shrugged, and lit another cigarette. 'But while he pursues these absurd fantasies of his, you are the one who will earn an Iron Cross in England. It is you who would make your father proud.'

Perhaps, Ernst thought. If he ever got there.

A band of soldiers came into the bar. There was a good deal of laughter and banter, despite the sirens. Their uniforms were soaked to the knee by sea water, as if they had been paddling.

It was as if everybody was playing, Ernst thought, all along the Channel coast. You had to keep up a front that this was a serious operation; he'd never say anything else even to Claudine. But Ernst suspected that nobody really believed the invasion would happen, despite all this build-up. There were other ways to bring down the British, such as bombing them flat, or sinking their supply convoys and starving them out. No, the vast, unlikely barge armada would never be launched. Ernst would never see England, and he would have to earn his Iron Cross some other way.

He finished his cognac. And when they left, he gave the barman money to cover the damage to the table.

20 August

The siren's wail woke Mary with a start. For a moment she had no idea where she was. The night was hot, her neck was slick with sweat, and the room was pitch dark.

She rolled over, and her questing hand knocked painfully into a bit of furniture. But she found the small electric lamp, and fumbled for the cord. The lamp came on, shedding a dim low-voltage glow. This was her hotel room. She was in Colchester, her first night here. The windows had been blacked out by being pasted over with wallpaper – cheaper than blackout curtains. No wonder she was lost. And no wonder the room was so damn hot, with the windows stopped up like that.

She lay back for a moment, reluctant to wake fully. The siren continued to howl, and now it was answered by others, more remote. They sounded like prehistoric beasts, long-necked and lonely, calling to each other across some dismal swamp.

A fist battered the door, making her jump. 'Everybody out and to the shelter!' She heard running footsteps receding down the corridor. Doors slammed, voices murmured.

So she got out of bed. She took slacks from her suitcase, which she hadn't yet unpacked, and pulled them on over her nightdress, and took a jacket down from where it hung on the back of the door. She forced her bare feet into her flat sensible shoes.

She crammed her research papers inside her briefcase and slammed it closed. Her gas-mask in its canvas bag hung on the back of the small chair before the desk. She looked around for her handbag, lost in the dim lighting of this awful power-starved English summer. She found it under the bed, next to a chamber pot. It held her identity card, ration books and US passport, all her essential papers. Her only valuable was her wedding ring, which she was wearing. What else, what else? It wasn't her first air raid, the big attacks had been going on across southern England for a week or more, but the others had caught her in Hastings where she had been staying with George Tanner and Hilda during Gary's convalescence. Now here she was alone in a strange town, and she hadn't figured out her routine. She didn't even know where the nearest shelter was.

At the last minute she reached back to the sink, grabbed her toothbrush and stuck it in her pocket.

She opened the door. The corridor was even more dimly lit than her room, with light bulbs only sparsely placed amid gaping empty sockets. There was nobody about. She hesitated for a second, trying to remember the way to the stairs. Left, she thought. She hurried that way.

Still the sirens wailed. She wondered what her friends at home would think if they could see her now, fleeing for her very life down this shadowy corridor, her nightdress sticking out of her slacks. She dragged her fingers through her hair, trying to comb it roughly.

She came to the stairs, a shadowy well. Holding onto the banister she hurried down to the ground floor, decanting into a tiny, deserted reception area. She ran straight through and out onto the street.

The night was cloudy, the sky dark. She was in utter darkness; she felt very uncertain. The streetlights were all out, of course. The only scraps of illumination came from the odd open door or imperfectly blacked-out window. She could smell dust and ash in the air. She was only a block or so from the big old Norman castle, but she couldn't even see that.

A big ack-ack gun opened up somewhere nearby, making her flinch, and the ground shook, the noise a battering roar. And somewhere to the north a searchlight splashed a circle of light on a lid of low cloud. More gunfire barked, and a stream of sparks rose along neat parabolic arcs. By the searchlight's glow she saw a family running in the dark, hunched over, parents hanging on to the hands of their children. Scuttling in the shadows they looked like rats.

Mary set off the way she thought led to the castle, her bag and gas-mask pouch over her shoulder, her briefcase in her hand. She could see practically nothing, and she groped her way along a wall. It was a nightmarish feeling, hurrying into the dark.

She collided with somebody. There was a stink of tobacco and stale beer. 'Hello, love. Lost your way?' A hand fumbled at her waist.

She slapped the hand away, hard. 'Fuck you.' She stepped out into the street.

'Well, I wish you would.' Clearly drunk, the man laughed, but didn't try to grab her again.

When she was well past him, she made her way back to the sidewalk and the wall. She tried to hurry; she sensed she was in more danger from the horny drunk than from the might of the Luftwaffe. Then she tumbled into a doorway, and fell. Her right hand scraped down the wall and her knee slammed into the paving stone. 'Shit, shit.'

A dim light floated before her, a masked torch. 'Are you all right?'

Mary looked up. She made out a woman's face. She wore a tin helmet and a dark overcoat with an ARP armband. 'I'm OK. I just tripped.' She tried to stand, but the knee was painful, and she winced.

'Let me help you.' The girl got hold of her under her armpit and hauled her to her feet.

'Thank you. I was just trying to get away from an asshole back that way.'

'There are plenty of those about. Hey, you have blood on your hand. That's a bit of a scrape. Well, you need to get to the shelter. Do you know the way?'

'No.' Mary looked around, and realised she had got turned about. 'I'm not sure which way is which, to tell you the truth.'