Ma warned her that anything she might overhear was subject to something called the Official Secrets Act, which meant that she wasn’t allowed to breathe a word about it to anyone, not even other members of staff. Of course this only intensified her curiosity, and she listened as best she could from the serving table, trying to glean any hint of what all these men were doing here, cloistered in this extraordinary place, and how they all related to each other.

The RAF officers had slight variations to their uniforms – she made a mental note to ask Mark later what all the insignia meant – but the civilians were harder to distinguish. The men in overalls were the noisiest, joshing each other and generally having a laugh. The quietest and most reserved were the men in suits, about fifteen of them, definitely the least gregarious and curiously mismatched; a real range of ages and types.

From the way they seated themselves she could sense the level of rivalry, even mistrust, between them. They talked quietly, huddled inward towards each other, so that it was impossible to make out a single word. Which was a pity, Kath thought, because she felt certain that these men were the brains behind the big secret, the masts and the high security.

Then, returning with a fresh pot of stew, she recognised him: small, dark-skinned and slight-framed, with an untidy shock of thick hair as black as she’d ever seen, keeping company with a much taller, broader older man, slightly balding, with an easy smile.

‘Hello again,’ she said. ‘I think we met at the station a while ago? And at the pram race?’

‘Ah, yes. Hello.’ Once more, she couldn’t tell whether that expression of slight amusement was shyness or genuine friendliness. She noticed that he refused the stew, taking only vegetables and a slice of cheese.

‘I’m Kath,’ she said. ‘Just started work here today.’

Her mother’s sharp whisper halted the exchange. ‘Stop yakking and get another plate of vegetables, please. We’re running out.’

As the queue moved forward, the older man nudged his friend in the ribs. ‘You’re a dark horse, Mac,’ she heard him say. ‘Pretty girl like that and you never said a word.’

The head chef, Mr Brunetti – a man of Italian heritage with charming manners and a rather short fuse, Ma warned – invited her into his office at the end of the shift.

‘Ah, Miss Motts, take a seat,’ he said. ‘I’ve heard very good things about your work today.’

‘Thank you.’ Clearly he’s noted my remarkable potato-peeling skills, she thought to herself, trying to keep a straight face.

He reached forward, taking up a sheet of lined yellow paper from his desk. ‘But I’m afraid there’s a bit of a problem.’

She’d seen this type of paper before, and knew at once what he was going to say next. Now that she was about to get the sack, the job suddenly seemed more appealing.