“When do you sit for Cambridge?” asked the American.

“Immediately I return. They think I’ll get in without any difficulty.” The boy knew that the assessment had already been sent, along with his end-of-term report, to his father. It was going to be a pleasant holiday.

The road began to fall away for the final descent into Zurich; from the elevation it was possible to distinguish the newness of the Bahnhofstrasse set against the tangled parts of the old quarter. The driver was familiar with the route and turned away towards the airport, missing the congestion of the town. Azziz detected the black spot of a helicopter and wondered if it were his; it was too far away to see the markings.

“We’re in good time,” said Williams, as the car turned onto the slip road to the airport. He wasn’t a good flyer and put a travel pill surreptitiously into his mouth. He hoped Azziz hadn’t noticed.

There was a separate car park for the private section, away from the main airport complex. When the car halted all three men turned instinctively towards Azziz. This was a mistake. So, too, was leaving the doors unlocked. All four opened simultaneously, the ambush perfectly coordinated.

“Move and he’s dead,” said a voice.

The. 375 Magnum was against the front of Azziz’s head, so all three men could see it; fired from that close, it would have decapitated him. The three remained motionless. It took only moments to disarm them. Williams had a Colt automatic in a shoulder holster and a short-barrelled Smith and Wesson against his leg in an ankle strap. The Arabs each had a Smith and Wesson, both long-barrelled.

“Take me too,” said Williams. His head was tilted awkwardly because a pistol was hard beneath his left ear.

“Don’t be stupid,” said the man who had first spoken. He was short and slightly built, olive-skinned and crinklehaired.

One of the Bedouin said “Pig” in Arabic. In the same language the spokesman said, “Tell his father that; tell his father we’re the worst pigs he can imagine.” He came back to Williams. “You listening?”