Stafford grunted and wondered about that but did not let it worry him. The time to worry was when he thought it might cause trouble. Hunt said, 'Do you mean Nair Singh?'

'Yes,' said Stafford shortly, and watched the island ahead.

At last they drew alongside the rocky foreshore and were able to land. Chip came down to meet them. He looked at the Hunts and frowned, then said to Stafford, 'Could I have a word with you?' Stafford nodded and they walked out of earshot. 'I don't think this is a good thing, Max. Why did you bring them?'

'I didn't bring them,' said Stafford irritably. 'I wanted Hunt along; his sister came without invitation.'

'But why even Hunt?'

'We've got to have someone on the inside and I elected Hunt,' said Stafford. 'I have my reasons and I'll justify them. Curtis tells me you've brought along your own surprise.'

Chip nodded. 'You'll forgive me if I don't introduce him. He's here… er… incognito.'

'One of your bosses?'

Chip smiled. 'Could very well be."

'So that's why we're here on an island,' said Stafford. 'All right; let's get on with it. We have a lot to discuss.'

Chip hesitated, then nodded. 'All right; let's go.'

Stafford jerked his head at Curtis and the Hunts and they all followed Chip up a slope which led down to the beach, walking among trees. Once Stafford was alarmed as a big animal broke away from quite close and he saw a white-ringed rump as it plunged away from them. 'Waterbuck,' said Curtis dispassionately.

'They do very well here,' said Chip. 'They swim across from the mainland. The big cats don't like water very much, at least not to the extent of swimming a mile, so the water-buck are safe from predators.' Stafford thought with some humour that even now Chip could not resist acting the courier, but became alert when Chip said, 'Watch out for snakes.'

They pressed on and eventually came to a piece of level ground on which were the foundations of a building. Whether the building had fallen down or whether the builder had just got as far as putting in the foundations Stafford could not decide. Here, waiting for them, were the others – Nair, Hardin and a stranger. He was an elderly black Kenyan with greying hair and an expressionless face. Chip went over to him and talked in low tones.

Stafford walked over to Hardin. 'Hello, Ben. Who's the old man there?'

'He doesn't say – neither does Chip. I'd say he's top brass. He doesn't talk so you'd notice.'

'He's come to assess the evidence,' said Stafford. 'I have some to give him.'

Chip stepped forward and said to the Hunts, 'I think we ought to introduce ourselves. I'm Pete Chipende, but call me Chip. This is…"

'No!' said Stafford sharply. 'Let's not pussyfoot around.' He looked at Alan Hunt. 'This is Colonel Peter Chipende of the Kenyan Army.' There was a flash in Chip's eyes which he ignored. 'You already know Nair but you don't know his rank and neither do I.'

Nair stepped forward. 'Captain Nair Singh, at your service.'

Hunt raised his eyebrows. 'I didn't know you were in the army, Nair.'

'You still don't know,' said Chip flatly. 'This conversation isn't happening. Understand?'

Stafford said, 'Ben Hardin you've already met, and this is Curtis. That gentleman over there I don't know, and I don't think I want to know. Chip is right. What you learn here you keep under your hats.'

Judy laughed nervously. 'All very portentous.'

'Yes,' said Hunt. 'Very cloak and dagger. What's it all about?'

'Tell him, Chip,' said Stafford.

Chip said, 'We have reason to believe that Ol Njorowa is not as it seems, that it is an illicit base in Kenya for a foreign power – a centre for espionage.'

'You're crazy,' said Hunt.

'Alan, you haven't heard the evidence. Wait for it.' Stafford turned to Nair. 'Have you got the photographs?' Nair gave them to him and he said, 'You produced these damned quickly.'

'My brother-in-law is a photographer. He did them.'

Stafford grimaced. 'That joke is becoming pretty thin, Nair.'

'But it's true,' protested Nair. 'My brother-in-law really is a professional photographer in Naivasha. He says because he did them so quickly they won't last; the colours will fade. He's doing a more permanent set now."

Stafford flipped through them. 'These will do for now.' He sat on the edge of the crumbling concrete foundation and began to lay them out. 'As he did so he said, 'Has anything happened I ought to know about, Chip?'

'Not much, except that someone was inquiring about Gunnarsson at the New Stanley. He wasn't there, of course; he was already in the hotel here.'

'Who was being inquisitive?'

'We don't know yet. It's being followed up.'

Stafford had got the photographs spread out. 'Right. These are pictures taken of Ol Njorowa during an overflight in Alan's balloon this morning. Anyone got any comments?'

He drew back to let the others inspect them. They crowded around except for the elderly Kenyan who had seated himself on a nearby rock and was placidly smoking a pipe. There was silence for a while then Hardin said, 'Yeah; this tower here. What is it?'

'That's the water tower,' said Hunt. 'The water is pumped up there and then distributed by gravity.'

Curtis coughed. 'Perhaps I could point out to the Colonel that the water tower is in the wrong place.'

'Why, Sergeant?'

'The natural place to build a water tower would be on the highest point of land.' Curtis pointed at another photograph. 'Which would be about there.'

Hunt looked at Stafford curiously. 'Are you a colonel, too?'

'I'm trying to retire but Sergeant Curtis won't let me,' said Stafford dryly. 'All right, a water tower in the wrong place.'

Hardin picked up the photograph. 'It's close to the perimeter fence where it angles. I'd say it's an observation tower. From the top you could cover a hell of a lot of that fence. Good place to put a couple of TV cameras.'

Chip said, 'What about at night? Is the fence illuminated?'

'No; I checked,' said Stafford.

'Could be infra-red,' said Nair. 'You couldn't see that.'

'No infra-red. You're behind the times, Nair. If there is TV coverage of the fence they'd probably use photo-multipliers – the things they use as night sights in the army. Even on a moonless, cloudy night you get a pretty good picture.'

'Are you serious about this?' demanded Hunt.

'Very.' Stafford waved his hands over the photographs. 'Anything else?'

'Yeah,' said Hardin. 'But it doesn't show in these pictures.' He turned to Hunt. 'You said a leopard was getting over the fence and that's why there was an armed guard. Right?'

Hunt nodded. 'Brice had a patrol out. He reckoned the leopard was getting over by climbing a tree which was too near the fence.'

'Yeah, that's what you said.' Hardin jerked his head at Curtis. 'Tell him, Sergeant.'

'Acting on instructions of the Colonel I did a tour of the perimeter from the outside. The vegetation has been cut back on the outside of the fence to a distance of at least thirty feet. There is no tree near the fence. I found evidence of weed killer; there was an empty paper sack. I didn't remove it but I made a note of what it was.' He took a piece of paper and gave it to Stafford.

'Pretty powerful stuff,' said Hardin, looking over Stafford's shoulder. 'It's the defoliant we used in Vietnam, and it's now illegal for commercial use. It looks as though someone wants a clear view along the fence.'

'How long is the fence?' asked Stafford.

'About six and a half miles, sir,' said Curtis.

'A ten foot chain-link fence six and a half miles long,' commented Stafford. 'That's pretty much security overkill for an innocent agricultural college short of funds, wouldn't you say, Alan?'

'I hadn't really thought of it in that light,' said Hunt. 'It was already there when I came to Ol Njorowa." He shook his head. 'And I hadn't noticed the cleared strip on the outside.'