At two o’clock one morning, with the waning moon no more than a silver sliver, Kungu Kabaya and Wilson Gitiri crouched in a drainage ditch that ran beside a dirt road. Across the way stood a small mud-brick building with a corrugated iron roof: the local police station.

Three weeks earlier, workmen had erected a second building. It was a low, squat structure made from reinforced concrete and it stood about twenty yards away from the station. Wooden posts, ten feet high, had been driven into the ground at regular intervals, forming a perimeter around the new structure. Barbed wire was strung between the posts to form a protective fence, with a double gate facing the police station, also constructed of wooden poles and barbed wire. It was secured by a heavy chain.

A convoy of trucks had come and gone. Their cargo had been unloaded. The natives who transferred a stream of heavy wooden crates from the trucks to the new building were believed to be loyal to their white masters. The contents of those cases were supposed to be secret, as was the purpose for which they were intended. But the terrifying power of the blood oaths outweighed any loyalty to the Crown, and there were precious few secrets from the Mau Mau any more.

Kabaya checked his watch. ‘Go,’ he whispered.

Gitiri raised his head above the side of the ditch, looked around to make sure no one was watching and ran across the road, bent low, before coming to a halt beside the fence. He was carrying a pair of long-handled cutters. They made short work of the barbed wire and Gitiri fashioned an opening big enough for a man, or a case filled with rifles, to get through. He turned towards the ditch and gave a quick thumbs-up.

Seconds later, Kabaya was scurrying to his second in command, followed by three other men. All of them had empty army backpacks hanging from their shoulders.

One after another they crawled through the gap in the fence, then ran up to the bare concrete wall of the blockhouse. They were confronted by the only way in or out: a thick steel door as impervious to gunfire or hand grenades as the concrete around it.

It would take an artillery shell or a bomb to smash into the building. Kungu Kabaya had neither. Yet he believed that he could get in. He looked at his watch and muttered under his breath.

‘Come on . . . Come on . . .’

Maina Mwangi was the police constable on duty. The night watch had never traditionally been a particularly arduous task. The country around the police station was white-owned. The colonists drank too much. They committed too many acts of adultery for the tastes of the pious men and women who cooked their food, cleaned their houses, washed their clothes and worked their farms. But they were seldom guilty of criminal offences. And if any African stole anything from them, their white masters almost always administered their own rough justice without recourse to the police.