In the breaking dawn sky above the SSU building, the pilot of a four-seater Cessna was radioing Shoreham Tower.

‘Golf Bravo Echo Tango Whiskey inbound from Dover.’

The little airport was unlit, so only operated between the hours of sunrise and sunset. This plane would be one of the morning’s first arrivals.

‘Golf Bravo Echo Tango Whiskey, Runway Zero Three. How many passengers?’

‘I’m solo,’ the pilot said.

As Sergeant Whitlock showed the next section on the grid that her team members were to cover, they were all concentrating hard. None of them heard the drone of the light aircraft coming in low overhead, circling to make its landing approach to Shoreham Airport’s runway 03.

Private aircraft and helicopters came and went here all the time. As there were no international flights, there was no Border Control presence, or any Customs either. Incoming flights from abroad were meant to radio a request for a customs officer and a border control agent to attend, and to remain in their aircraft until both had cleared them. But that normally meant a long delay, often with no officers arriving anyway, so pilots sometimes took a risk and did not bother.

Certainly the pilot of the twin-engined Cessna was not intending to radio them. The flight plan he had filed last night was from Shoreham to a private airstrip near Dover and then back. He had omitted to include, on the plan, a minor detour across the Channel to Le Touquet in France and back – which he had made with his transponder switched off. For cash payments of the size that he was receiving for this trip, he was always more than happy to make omissions in his flight plans.

He taxied along the three-deep line of parked aircraft towards his parking space, happy to hear that there were several more incoming aircraft stacking up, which would keep the crew in the tower occupied. He turned in, manoeuvring his plane to the same angle as the others, then put on the parking brake and throttled back the engines. He looked around carefully for signs of anyone who might be taking an interest in them, then switched off both ignitions.

As the propellers spun down, the aircraft vibrated less and less and the noise diminished. The pilot removed his headset, turned to the beautiful, blonde German woman directly behind him and said, ‘OK?’

‘Sehr gut,’ she said, and began unbuckling her harness.

He raised a cautioning hand. ‘We have to wait a little.’ He peered anxiously out again, then turned to the tired-looking teenage girl, dressed in a smart white overcoat, on the seat behind the woman. ‘Enjoyed the flight?’

The girl didn’t understand English, but she picked up the gist of what he had said from his tone and nodded nervously. He unbuckled himself and reached over to help her out of her safety harness. Then he signalled for her to stay, climbed out and jumped down, leaving the door slightly ajar.

Marlene Hartmann welcomed the blast of cold, fresh air, even though it was laced with the smell of kerosene. Then she yawned and gave Simona a smile. The girl smiled back. A pretty little thing, Marlene thought. In another country, in different circumstances, life could have been good for her. She yawned again, longing for a cup of coffee. It had been a long, long night. By road to Belgrade, then a late flight to Paris, then a taxi at four in the morning to Le Touquet. But they were here. And she was happy with the plans.

Yes, after the visit from the police officer yesterday, it would have been more sensible to abort. But then she would have lost a good customer. She did not think the Detective Superintendent could move this fast. Everything would be done before he even knew it and by tonight she would be back in Germany.

Another plane was coming in to land and the pilot, standing outside, heard the roars of several different aero engines, including the clatter of a helicopter, and saw a convoy of three aircraft taxiing out towards the runways. Plenty to keep the tower occupied. This was always a good time of day, still a little bit of darkness and numerous distractions, including the vehicles of airport workers arriving.

The white van was parked a few hundred yards along, beside the perimeter fence. He stared at it, then pulled out his handkerchief and blew his nose.

Behind the wheel of the van, Vlad Cosmescu was watching. This was the signal.

He started the engine and put the van into gear.

Lynn Beckett sat, bleary-eyed from a sleepless night, her heart thudding, hunched over her kitchen table, sipping a cup of tea. She had lain in bed for hours, tossing and turning, shaking her pillows to try to get them comfortable, and getting up, obsessively, every twenty minutes or so to check on Caitlin, help her to the loo, ensure she drank glucose water and took the antibiotic tablets. The combination Ross Hunter had prescribed, probably aided by the jab, seemed to be working. Caitlin’s pain had subsided and the itching was a little less bad.

For a long time after the doctor’s visit, she had remained downstairs with Luke. They had downed a bottle of Sauvignon Blanc and smoked their way through an entire packet of Silk Cut, sharing the last cigarette between them.

Now her head was pounding, her lungs were raw and she felt terrible. Luke had finally fallen into a deep slumber in the chair beside Caitlin’s bed.

The television was on. She stared at the 9 a.m. news, but she had no interest in it. Nor in the programme on helicopter rescues that followed. She had no interest in anything, at this moment, except for the phone call she was waiting for from Marlene Hartmann.

Please call. Oh, please God, call.

She did not know what she would do if the German woman did not make contact. If she had simply conned them out of the money. She had no Plan B.

Then, suddenly, the landline phone rang.

She answered it before it had completed the first ring. ‘Yeshello?’

To her relief, it was Marlene Hartmann. ‘How are you today, Lynn?’

‘Yesfine,’ she gasped.

‘Everything is good. We are here. You will be ready for collection?’

‘Yes I will.’

‘The payment is in order? You have the balance ready?’

‘Yes.’ She swallowed.

Her bank manager had already queried the first transfer she had made, and she had given him a lame reason that she was buying an investment property in Germany, from a one-off-payment final divorce settlement from her ex-husband, following an inheritance he had received.

‘You will see us later. The car will arrive for you as scheduled.’

She hung up before Lynn could thank her.

The car was scheduled for midday. Less than three hours.

She was so wound up with stress, fear and excitement, she could hardly think straight.