Bannerman felt crushed. He thought about what du Maurier had said. There were so many conflicting bits and pieces, of fact and assumption. All that was clear was that someone had hired a man called Kale to kill Gryffe and Slater, and to make it look like a quarrel. When it became apparent that Tania had witnessed the murders, she had become the next target. But if you eliminated Jansen and Lapointe, and if you ruled out the government in London, who else had a motive? And then, why did the man, Kale, not kill Tania at the clinic when he had the chance? Or at almost any other time? Why choose a busy airport where he had little or no chance of getting away with it?

‘Is there anything among Kale’s belongings . . .?’

Du Maurier shrugged. ‘Nothing that means anything to me.’ He opened his desk drawer and pulled out a large polythene bag full of Kale’s personal effects. ‘He was carrying these about his person. There was nothing in his case but clothes.’ He emptied the contents on to his desk and Bannerman pulled his chair closer.

There was a holster, a wallet with some money and a chequebook. A passport, a pen, keys, some loose change, a pack of cigarettes, a tattered map of England, a lighter and a scrap of paper. Du Maurier lifted the piece of paper and handed it to the reporter. Bannerman read the three words and dropped it on to the desk as if it had burned his fingers. And in that moment he thought perhaps he understood why Kale had not attempted to kill her sooner.

‘We’ve checked it for prints. Clean, except for Kale’s.’

Bannerman surveyed the killer’s personal items with a stultifying hopelessness. He might have carried any of these items himself. Except for the holster. Du Maurier opened out the map and spread it on the desk. ‘You may want to take a look at this.’

It was a large-scale map, well thumbed, tearing at the folds. Bannerman’s eyes were drawn by a red line connecting two circles drawn with a felt pen. The first encircled a small Lancashire town near Southport, from which the red line followed the A565 north past a place called Crossens, before veering off in a short stroke to the west and the second circle. The words ‘big house’ were written in small letters beside it, followed by ‘farm track’ and ‘bridge over water’. In the margin, written in green ink, was the word ‘Lamb’, followed by a large question mark. For a few seconds Bannerman stared at it without understanding. Then suddenly he made the connection. His heart quickened and his face flushed. He looked up at du Maurier, who raised an eyebrow. ‘It means something to you?’

‘Can I use your phone?’ He needed to double-check.

‘By all means.’ The policeman got him a line.