Delphine picked out a hard brown candy and sucked on it, glad of the distraction. The sweetness was so intense she felt a headache coming on.

Miss DeGroot closed her eyes. She extended her arms and slid them up and down like someone making a snow angel.

'We must seem ancient to you. Do I seem ancient?'

Delphine glanced at Miss DeGroot. Up close, she did look older. Fine cracks radiated from her eyes and her skin had the sickly cast of semolina. Her blond hair was thinning at the scalp.

'No.'

'You're a sweetheart. And a liar.'

Delphine bit her lower lip.

'Do you love Mr Propp?'

One of Miss DeGroot's eyes snapped open. 'That's a very strong word.'

Delphine wrinkled her nose.

'I'm sorry.'

'Don't be. I'm your guest. It was a fair question.' Miss DeGroot squinted at the corrugated-iron ceiling. 'I should say all Spim is founded on the doctrine of amour-Propp. Of course, Ivan says that none of us can love not while we're asleep. Oh, we all think we do. But when you look at it, what we call "love" is just a cat's cradle of demands and rewards. Real love doesn't make you feel good. You have to pay. Real love is sacrifice. It costs you.' She let out a short, mirthless laugh. 'Huh. Perhaps I do love him.'

Delphine drew in the dust with her fingertip. 'You don't think he's wicked?'

'Now, what on earth would make you say that?'

Delphine felt her face getting hot. 'I heard somebody say so.'

'Who?'

'I don't remember.'

Miss DeGroot's gaze hung on Delphine a moment longer.

'Well, maybe they're right. Maybe everyone we place our trust in is destined to betray us. I honestly don't know any more.' She draped a forearm over her face. 'Oh gosh, he's really done a number on our heads, hasn't he?'

'What about Dr Lansley?'

'What about him?' Miss DeGroot slid her arm from her eyes. 'Young lady, I do believe you're trying to shake me down for gossip.'

'No, I'm just . . . I . . . ' Delphine clenched her fists, breathed in. 'Can you keep a secret?'

'No.'

'Oh, uh . . . '

'But at least I'm honest.' Miss DeGroot lifted herself up onto her elbows. 'Look, I know the Doctor isn't exactly a teddy bear, but he's not good with . . . well, anyone, really. Try not to take it personally. You know he saved dozens of lives during the war? Lost his hearing, too. Small wonder he's a little cranky.'

'I have evidence suggesting Mr Propp is a spy.'

'Is that your secret?'

Delphine nodded. 'And I think Lord Alderberen and Dr Lansley are in on it.'

Miss DeGroot tilted her head forward. 'Why are you trusting me with this?'

'I don't know. I thought . . . you might believe me.'

Miss DeGroot closed her eyes. She smiled and brought a finger to her cheek. A tear rolled over her knuckle.

'You're a nice girl, you know that?' She sat up. 'Okay. Tell me about it.'

Delphine told her everything. She talked about the secret passages and tunnels, about overhearing Propp and Lord Alderberen on the first day, she even after picking at a splinter in the floor admitted to opening Propp's post and finding the letter from Mr Kung. All the while, she monitored Miss DeGroot's face for signs of scepticism, anger, or boredom. Miss DeGroot nodded and watched. She did not smirk.

'He left this on the beach.' Delphine slid the folded paper from her sock. 'It was wrapped round a book my father took.' As she passed it to Miss DeGroot, she realised that her hand was shaking. 'I can't read it.'

Miss DeGroot studied the page. She folded it in half, running her thumb along the crease, and lay it on the floor beside her.

'You must be exhausted.'

'I don't know what to do.'

'Listen.' Miss DeGroot reached out and closed her fingers over the back of Delphine's palm. They were soft and clammy. 'I believe you.'

Delphine breathed out long and hard.

'I believe everything you've told me.' Miss DeGroot gave Delphine's hand a squeeze, then let go. 'I know it's hard to understand, but all the adults here . . . we're broken. Me, the Doctor, Lazarus, your father. Look at that professor of yours, shut away in the chimera room, surrounded by beasts while he waits on a letter from the latest handsome young undergraduate he's mooning over. Dreaming of a hidden country they can run away to together.' She shook her head. 'The island of Dr Morose!

'I'm sure those men like to dream they could take over the world. Making trunk calls at the dead of night, playing kingmakers. But that's all they're doing playing. Maybe Ivan really is a spy, who knows? If he is, this is the best place for him. Away from London, away from anyone of any influence whatsoever.'

'But . . . '

'The symposium? Oh, darling, no one of any account goes there. Important people are too busy running the country.'

Delphine sagged. 'You think I've imagined it all.'

'No. Absolutely not.' She picked up Mr Kung's notes. 'I'll look at this. I'll think on what you've said. And if you find anything more, or . . . you just need somebody to talk to, you come find me, you hear?'

Delphine placed her hand flat on the floor. She could feel her palm pulsing against the warped wood.

'All right,' she said.

Miss DeGroot stretched and yawned.

'Why were you cry '

Delphine was cut off by approaching voices. Miss DeGroot scrambled into the crow's nest. She grabbed a leafy branch and pulled it down across her face. She beckoned for Delphine, who joined her on the battlements.

Down in the woods, Dr Lansley was pushing Lord Alderberen in his wheelchair. The wheels eek-eek-eeked as they traversed bumpy ground. Lord Alderberen clutched a tartan blanket spread across his knees. Walking alongside, hands tucked into the pockets of his silk waistcoat, was Propp.

'Speak of the devil,' said Miss DeGroot. 'Here come the girls of Radcliff Hall.'

'What?'

'Shh!'

The wheelchair progressed in a succession of jerks and hiccups; Dr Lansley was grimacing with the effort. The sound of snapping twigs grew louder. She could make out Lansley's part of the conversation, since, as usual, he was noisiest.

'Well, that's as maybe, but . . . No, it's not that I disagree, I just . . . Well, I'll have to take your word on that, won't I, because as you keep telling me, I can't make the trip. Damn it, Lazarus, can't you wheel yourself for a bit? It's like ploughing treacle. Steady, there's a dip here . . . '

Delphine glanced to her right. Miss DeGroot had vanished. She heard footfalls on the hollow floor and suddenly Miss DeGroot was beside her, brandishing the shotgun.

'What's the betting I can still hit Titus in the backside at thirty yards?'

'No!'

'What, don't you think I can manage it?' Miss DeGroot barged her way into the crow's nest. 'Come on. I bet you a pack of Du Mauriers. Right in the hiney.'

'Please, you can't.'

'Pshaw! Just watch me.' She swung the gun towards the approaching trio and squinted down the sights.

Mr Garforth had made Delphine swear to keep her gun unloaded unless preparing for a shot. She would never dream of breaking her word, but experience had broadened her definition of 'preparing'. After all, shouldn't she always be prepared? When the perfect bird presented itself, she didn't want to be fumbling for cartridges. In a sense, her whole life was a preparation for the next shot, and thus the only true negligence was leaving her shotgun unloaded.

Miss DeGroot inhaled.

'Pull.'

Delphine slammed her forearm into the muzzle just as it kicked. The right barrel sent up a tremendous report. The shot rang through the woods, goldfinches scattering. She saw, through smoke and falling leaves, Dr Lansley sprawled face down in the dirt.

Delphine stared. The treehouse seemed to lurch.

A second later he was staggering to his feet. The shot had gone comfortably wide.

'Jesus Christ!' Slapping earth from his tweed lapels. 'Jesus Christ, what the Hell was that?'

Delphine dropped into the sanctuary of the crow's nest. Miss DeGroot lay on her back, hands clamped over her mouth, laughing silently till the tears streamed into her hair. The woods echoed with Lansley's swearing.

'Oh my,' she said. 'Oh my, girl. That was fun.'

CHAPTER 13.

BIG GAME.

July 1935 Delphine followed Propp round the north shore of the lake. He was climbing a small hill on the water's edge, towards a dome of grubby, mossy brick. The maps all referred to it the same way: 'the ice house'.

She sliced through a black clump of candlesnuff fungus with her crab stick. In the late evening sun, the woods rippled with amber light.

Mr Propp's disappearances were beginning to bleed into one another. He was away more than he was present. He sometimes talked vaguely about seminars in London, but he never took a motor car Delphine had checked and the station was too far to reach on foot, especially for one so old and portly.

After dinner, when Propp pulled on a dark grey greatcoat, slid his stick from the bronze umbrella stand and left the Hall through a side door, Delphine followed him. She kept her distance, pantomiming intense absorption in flowers or clusters of reeds. She watched him through the field glasses. They were still speckled with sand from the beach. When she twisted the focus knob, it crunched.

At the crest of the hill, he stopped. Delphine crouched in a patch of yellow rock-rose, congratulating herself on her consummate veldt-craft. Propp shielded his eyes as he looked back towards the Hall. Above him, great anvil-shaped clouds hung with scarlet and magenta peaks and dark underbellies. In the dwindling sun, his tanned, bare head winked like a doubloon. When he turned and continued round the far side of the ice house, out of sight, she balled her fists.

He was unaware. She had him.

She waited for him to reappear.

Five minutes passed.

Delphine began to get fidgety. She had cramp in her thigh from squatting. She threw glances into the woods. What if he had circled round?

She sat. Something flickered in the trees. A red squirrel was corkscrewing up the trunk of a horse chestnut. She pressed a palm to her chest, exhaled.

Ten minutes passed. No sign. He had vanished.

Delphine stood as casually as she could. She made a point of not looking towards the ice house. Her right leg throbbed with pins and needles.

She ambled to the lakeside, pretending to admire the way the orange sun flowed molten into the water. Gnats seethed above the rushes. She scythed through them with her crab hook, then turned and began wandering up the hill.

Up close, the ice house was in even worse repair than the tomb. Spurts of yellow stonecrop dangled from cracks in the age-blackened brickwork. Moss clung in dark, sweaty clumps. Set deep in an embrasure was a door.

It was made of thick oak planks banded with black iron. Above a three-inch keyhole was a door knob bigger than her fist.

Surely Propp hadn't gone inside?

She scanned the lawns, the distant driveway. They were deserted.

Delphine knelt and peered through the keyhole. Blackness. She listened. Silence. She sniffed. Musty sourness.

She stood and stared at the door. There had to be a way in.

She kicked it. Her heel bounced off the oak. It was like kicking a church. She brandished her crab hook and spent a few fruitless minutes trying to find some angle whereby she could fit it inside the keyhole and pick the lock.

There was probably nothing inside. The door looked rusted shut and the lock was so sturdy she doubted even a shotgun blast at point-blank range would shift it.

The light was fading. She shivered. Across the lake, Alderberen Hall was turning a dirty beige.

She gave in.

'The whole thing's a rum business,' Delphine said later that evening, lifting the kettle off the fire with her crab hook.