‘Fear me, you thief of cattle. Fear me, for I am your death!’ Loikot raised his staff, held it like a stabbing spear and advanced on the lion with a lithe, dancing step. Leon was amazed when the lion leaped to its feet, curled its lip in a threatening growl, then slunk away into the grass.

‘Did you see me, M’bogo?’ Loikot crowed. ‘Did you see how Simba fears me? Did you see him run from me? He knows I am a morani. He knows I am a Masai.’

‘You crazy tyke!’ Leon relaxed his clenched fists. ‘You’ll get us both eaten.’ He laughed with relief. He remembered Lusima’s words, and it occurred to him that, over the hundreds of years that the Masai had relentlessly hunted generation after generation of lions, their persecution had ingrained a deep memory in the beasts. They had come to recognize a tall red-cloaked figure as a mortal threat.

Loikot leaped in the air, pirouetted with triumph and led him on northwards. As they went, Loikot continued his instruction. Without slackening his pace he pointed out the spoor of large game as he came upon it, and described the animal that had made it. Leon was fascinated by the depth of his knowledge of the wild and its creatures. Of course, it was not difficult to understand how the child had become so adept: almost since he had taken his first step he had tended his tribe’s herds. Manyoro had told him that even the youngest herd-boys could follow a lost beast for days over the most difficult terrain. But he was fascinated when Loikot came to a stop and, with the tip of his staff, traced the faint outline of an enormous round pad mark. The ground was baked hard by the sun, and covered with chips of shale and flint. Leon would never have picked out the track of a bull elephant without the boy’s help, but Loikot could read every detail and nuance of it.

‘I know this one. I have seen him often. His teeth are this long . . .’ He made a mark in the dust, then paced out three of his longest strides and made a second mark. ‘He is a great grey chief of his tribe.’

Lusima had used the same description: ‘Follow the great grey men who are not men.’ At the time it had puzzled Leon, but now he realized she been speaking about elephant. He pondered her advice as they went on into the north. He had always been fascinated by the wild chase. From his father’s library he had read all the books written by the great hunters. He had followed the adventures of Baker, Selous, Gordon-Cumming, Cornwallis Harris and the rest. The lure of wild sports was one of the most powerful reasons why he had enlisted in the KAR rather than enter his father’s business. His father termed any activity not aimed specifically at the accumulation of money as ‘slacking’. But Leon had heard that the army brass encouraged their young officers to indulge in such manly pursuits as big-game hunting. Captain Cornwallis Harris had been given a full year’s leave of absence from his regiment in India to travel to South Africa and hunt in the unexplored wilderness. Leon longed to be able to emulate his heroes but so far he had been disappointed.

Since he had joined the KAR he had applied on more than one occasion for a few days’ leave to indulge in his first big-game hunt. Major Snell, his commanding officer, had dismissed his requests out of hand. ‘If you think you have signed up for a glorified hunting safari then you are very much mistaken, Courtney,’ he said. ‘Get back to your duties. I want to hear no more of this nonsense.’ So far his hunting had been restricted to a few small antelope, Grant’s and Thomson’s gazelle – known to all as Tommies – which he had shot to feed his askari while they were on patrol. But his heart stirred when he watched the magnificent animals that flourished all around him. He longed for a chance to go after them.

He wondered if by counselling him to ‘follow the great grey men’, Lusima was suggesting he should take to the life of an ivory hunter. It was an intriguing prospect. He went on more cheerfully behind Loikot. Life seemed good and full of promise. He had comported himself honourably during his first military action. Manyoro was alive. A new career was opening ahead of him. Best of all, Verity O’Hearne was waiting for him in Nairobi. Yes, life was good, very good indeed.

Five days after they had left Lonsonyo Mountain, Loikot turned east and led him up the escarpment of the Great Rift Valley into the rolling forested hills of the uplands. They topped one and looked down into the shallow valley beyond. In the distance something glinted in the late-evening sunlight. Leon shaded his eyes. ‘Yes, M’bogo,’ Loikot told him. ‘There is your iron snake.’

He saw the smoke of the locomotive spurting in regular puffs above the tops of the trees and heard the mournful blast of a steam whistle.

‘I will leave you now. Even you cannot lose your way from here,’ Loikot told him loftily. ‘I must go back to care for the cattle.’

Leon watched him go regretfully. He had enjoyed the boy’s lively company. Then he put it out of his mind and went down the hill.

The locomotive driver leaned out of the side window of his cab and spotted the tall figure beside the tracks far ahead. He saw at once from his ochre-red shuka that he was Masai. It was only as the engine puffed closer that the man swept open his cloak and the driver saw he was a white man in the ragged remnants of a khaki uniform. He reached for the brake lever and the wheels squealed on the steel rails as they drew to a halt in a cloud of steam.

Major Frederick Snell, officer commanding the 3rd Battalion, 1st Regiment, The King’s African Rifles, did not look up from the document he was perusing when Lieutenant Leon Courtney was marched under armed escort into his office in Battalion Headquarters.

Snell was old for his command. He had fought without particular distinction in the Sudan against the Mahdi, and again in South Africa against the wily Boers. He was close to retirement age, and dreading its arrival. On his army pension he would be able to afford only a mean lodging in a town such as Brighton or Bournemouth, which, for the remainder of their days, would have to be home for both him and his wife of forty years. Maggie Snell had spent a lifetime in army quarters in tropical climes, which had yellowed her complexion, soured her disposition and sharpened her tongue.

Snell was a small man. His once bright ginger hair had faded and fallen out until he was left with only a scraggly white fringe around a freckled pate. His mouth was wide but his lips were thin. His eyes were round, pale blue and protuberant, which justified his nickname: ‘Freddie the Frog’.

He replaced his pipe between his lips and sucked at it, making it gurgle noisily. He was frowning as he finished reading the handwritten sheaf of paper. He still did not look up, but removed the pipe from his mouth and flicked it against the wall of his office, leaving a splatter of yellow nicotine drops across the whitewash. He put it back in his mouth and returned to the first page of the document. He read it again with deliberation, then laid it neatly in front of him and at last raised his head.

‘Prisoner! Attention!’ barked Sergeant Major M’fefe, who commanded the guard detail. Leon stamped his battered boots on the cement floor and stood erect.

Snell eyed him with distaste. Leon had been arrested three days earlier when he had presented himself at the main gates of Battalion Headquarters. Since then he had been held on Major Snell’s orders in detention barracks. He had not been able to shave or change his uniform. The stubble on his jaw was dark and dense. What remained of his tunic was filthy and tattered. The sleeves had been ripped off. His bare arms and legs were criss-crossed with thorn scratches. But despite his present circumstances he still made Snell feel inadequate. Even in his rags Leon Courtney was tall and powerfully built, and he radiated an air of naïve self-confidence. Snell’s wife, who seldom expressed approval of anyone or anything, had once remarked wistfully on how fetchingly handsome young Courtney was. ‘He’s set a few hearts fluttering hereabouts, I can tell you,’ she had said to her husband.