McCallion felt the cold from the damp ground seep into his bones. During his snail like crawl through the cess pit of no-man's land his thoughts had been firmly fixed on the officer who was just a few yards ahead of him.

He could barely see Hartley in the all embracing darkness.

Ever since Andy Hollinger had innocently told him of Hartley's decision to collect the repaired clothing for himself, his suspicions about the officer had grown.

All the little pieces of a nightmarish jigsaw were beginning to come together in McCallion's mind. And, of course, the discovery of the lock of hair and the button in Hartley's possession had almost sent him over the edge.

He licked his lips in an attempt to bring some saliva to his parched mouth.

McCallion toyed with the idea of taking his suspicions to Captain O'Brien but he knew his evidence was more or less circumstantial. To besmirch the name of a respected officer on such flimsy evidence was unthinkable. And he also suspected that Hartley knew his secret had been uncovered.

He had to get that cigarette case away from Hartley. And he had to get back alive. If he was right and Hartley was aware of his suspicions, Bert knew he had to worry about more than the Germans.

Just feet away, Hartley rolled over into his back and stared into the inky blackness.

A shiver - not of cold - but of excitement, ran through his body.

He remembered finding the incinerator beside the aid post. No-one took any notice of him as he stuffed the bloodstained clothes into the furnace.

He slept soundly that night. The voices had not disturbed him at all.

Suddenly, there was a metallic clatter from the right and three men of the patrol knew that the fourth had snagged a trip wire. Cans rattled and the sound seemed to be amplified to bell-like proportions in the stillness of the night.

Murdoch buried his face in mother earth and prayed. His devotions went unheard and a scythe of machine gun fire cut through the air inches above his head.

Hartley reacted instantly and slithered back towards McCallion who had, by now found a fold in the ground which was the best cover available.

There was a scream as Murdoch and then Evans were caught by the methodical bursts of fire which swept the ground.

"Jesus," cried Evans. But the machine gunners failed to respect his beseeching call for divine assistance. They poured on the fire.

Then all was still. McCallion and Hartley were alone in the dark.