The helicopter came back to settle over their heads, blanketing all other sound with the roar of its engine, following sluggishly in their wake. At once the stalks were lashed into activity again, threshing furiously about as they were torn this way and that by the fluctuating down-draught. Progress became teeteringly slow and painful, the maelstrom threatening constantly to suck them off balance, to pitch them forward, or to hold them back and – by suddenly releasing its grip – cause them to be thrown down against the earth. And all the time the stalks lashed them, cracking down across their shoulders, breaking fiercely against their knuckles, beating them in the face, bruising their eyes, and, when they lowered their heads for protection, buffeting their crowns repeatedly. But they staggered on, MacConnachie obviously exerting every ounce of muscle and self-control to maintain his persistent, measured action.

And then Ansell understood suddenly what he was doing. Since the pilot could see them, MacConnachie was waging a psychological war, blatantly advertising the fact that he did not accept the dominance of the pilot’s position, insisting with his body that the initiative lay with them. It was an act of such arrogant insolence that Ansell felt uplifted with joy. The man was indestructible.

All at once the helicopter began to step up its harassing tactics, dropping lower, pulling out and sweeping back, trying to exert pressure on them; and MacConnachie was puzzled as to why. The pilot was too good to start that nonsense without reason – certainly he hadn’t been goaded into it; and yet, although he disguised his intention well, managing to give the impression that each jink and turn was caused by some natural phenomenon such as gusting wind, it was clear to MacConnachie that the pilot was perturbed. Why? They couldn’t be near the edge of the field yet; it simply didn’t feel like it.

And then, just like that, without warning, they fell out of the constricting stalks on to cropped field, with shoots no more than three inches high. It was so unexpected that they literally fell, shocked and blinking, blinded by the sudden piercing brightness of the sunlight.

As their eyes adjusted to the glare, they heard the chopper roar into a turn and bear down on them again. Ansell tried to make out the nature of the ground on which they crouched, while MacConnachie, he noticed, slipped the gun from under his tunic.

The cropping extended for about five feet, then there was a shallow irrigation canal of some kind, eight to ten feet across, with a further five feet of cropping on its far side, and beyond that the stalks rising up again across their front. They seemed to have come out into the side of a corridor that ran right across the field, down which they could look to left and right for a considerable distance before it turned on to a new path and cut off their view.