The helicopter came back, and the swishing sounds cut deep into the shallows around them. For far too long the search went on, the machine floating above them, slipping sideways, floating again, passing over and above and below their position a dozen times, never leaving their field of vision, persistently a danger to them. Ansell could hear MacConnachie cursing and shifting restively. He knew why. So long as they were trapped here, unable to move, the force that must already have crossed the river in pursuit of them would close the net ever tighter to their rear. At last the helicopter, maintaining its pattern of search, disappeared from view over the ridge above; but the sound of its blades came back, cutting and vicious, a probable companion for the rest of the day. MacConnachie rose at once.

‘Let’s get on, for God’s sake! We’ve lost an hour!’

He tried to increase their pace, but the terrain wouldn’t cooperate. Beyond a certain point, their boots found no purchase in the scrub: they fell into an angry, flurried labour up the scarp. All the time the sounds of the helicopter tormented them, suddenly increasing in volume so that they thought it had turned back, and then diminishing as they unlocked painfully from the conditioned stillness into which they had frozen. At one point, MacConnachie lost his grip on the suitcase, and it was only by chance that it fell at the feet of Ansell who, without looking, trapped it automatically. Otherwise, they would have had the entire feature to climb again.

Thirty feet below the crest, the angle of ascent increased so drastically that they were forced to crawl. By the time they reached the summit, they were hot, dirty and exhausted, and had lost even more time.

MacConnachie had been right. This was the first of two main spinal ridges. The second lay directly ahead, right across their front, fifteen to twenty miles away.

Between the two was a wasteland of smaller hills, scarps, gullies, shelves and scrub. This was the first area of maximum danger. During the next twenty-four hours, the odds would always favour recapture rather than escape.

The helicopter was about a mile ahead, below their present height, continuing to execute its neat, untiring patterns. Ansell said, reaching for breath,

‘Shall we take a chance and keep moving?’

‘We’ve got to. How well can they see out the back of those things?’

‘Not well. It’s an early model. Boxed-in. They have to stick their heads out to look back.’

‘They won’t do much of that. Let’s move.’

The first stretch was downhill to a gully. As he led the way, MacConnachie called back over his shoulder,

‘You see the main ridge on the horizon?’

‘Yes.’

‘There’s a secondary height, two thirds of the way there. Got that?’

‘It’s got two pimples on the top.’

‘That’s the one. Well, that’s our objective for today.’

‘Oh,’ said Ansell. ‘Right.’

It looked a hell of a long way.

For three hours they laboured in silence, following in the wake of the dancing aircraft, crossing gullies, ascending slopes, descending them with greater care for they were then exposed, always trying to maintain an all-round watch and an even pace. The sun rose steadily to its height, and the heat grew more oppressive; sweat ran from them without pause. The suspicion grew in MacConnachie’s mind that they had been spotted.