“I’ve a problem, Max.” The other man took a simple pleasure in Sir Derek’s discomfort. It was rare the PUS admitted to a chink in his Service and he ordered a savoury.

“When you say Wavery in Abyla is not up to snuff – correct me if I’m wrong, Derek, but you chose him yourself.”

“I tell you we were all very pleased when Wavery got the job,” Sir Derek said. “He used to be one of our bright young stars.” He stopped. Max, too, had been on the Appointments Board.

“Well then?” Max waited, amused. He had been one of Cullis’ bright young stars himself.

Cullis pushed away his plate. “His eye’s not on the ball. He’s in love, Max.”

“Are we still talking about Catharine Riding?”

“What do you mean ‘still’?”

“I never know, Derek. You diplomats . . . ”

Cullis ignored him, releasing one of his chill Scottish sighs. “Since you know everything, how is Mrs Riding?”

“Interesting you should ask that. She was seen, only very recently, in a travel agency.”

“Don’t tell me, booking her holiday in North Africa.”

“I think we may assume so.”

“You go up, Max. I’ll settle this.”

“White or black?”

“Black, no sugar,” said the Permanent Under Secretary.

The other man walked to the library on the first floor. From a Portuguese waitress, he accepted two cups, dropping into his own a single saccharine tablet. He looked for seats and managed without spilling the coffee to overtake a bishop on his way to the sofa.

Sir Derek squeezed onto the sofa beside him. They sat in silence looking at the greying sky. Cyclical becoming westerly, escalating to gale force eight, reckoned the Permanent Under Secretary.

After a while he said, “You’ve heard the PM’s latest angle on the tunnel?”

“The Trojan Horse theory?”

“You are up to date, Max,” he said grudgingly. It unnerved him that his protégé enjoyed direct access to the Prime Minister. It was something he had learned to live with. There would have been mayhem if they hadn’t got on. “It’s irritating the PM should be so interested.”

“Do you share his belief?”

“That we could be overwhelmed by illegal immigrants? If they chose to be difficult, who knows what the Berbers would do.”

“Is there anyone who knows what they’re up to?”

“Unfortunately, Worsnop in Rabat has had to take early retirement. We haven’t chosen a successor.”

“So Wavery in Abyla is your nearest man?”

“You see, Max, he’s the one we have to rely on.”

“Could you recall him?’

“Six months before the Royal Visit? Too embarrassing. No, I badly want someone who knows the place inside out. When the tunnel is up and running we’ll need to monitor the Berbers. I need your help, Max.”

Max’s gaze returned through the empty trees. “I wonder who our agent is down there.”

After a professional relationship extending ten years, the PUS was never certain how much Max knew, how much he pretended not to know.