There was more distorted chat from the earpiece.

‘Right,’ he snapped and dropped the phone back in its cradle. He sniffed. ‘As I thought. It’s from some green-belt land just off the motorway on the road to Huddersfield. It’ll have been discovered and thrown away. If the gang’s as professional as you said it was, it would be wary of tricks like that.’

Angel pursed his lips. Maybe. Maybe not. Anyway, in his experience, when tracking devices had been found by crooks, they used to transfer them to a different vehicle. It amused them to think of the police tailing some innocent lorry or bus driver pointlessly around the countryside.

‘I want you to get that girl and her infant out of Beechfield Walk. Let WPC Baverstock get back to her duties, and you get back to those two unsolved murder cases. You’ve got plenty on your plate, lad.’

‘Yes, sir.’

Angel drove the BMW northwards on the road towards Huddersfield. Sitting next to him was Gawber who was looking at a laptop monitor showing the map and flashing co-ordinates indicating the whereabouts of the Mercedes. The flashing arrow on the screen showed that they needed to move west and north, so Angel left the main road and was directed to travel up a narrow unmade road, like a cart-track, almost parallel to the motorway. It was built up on the left like the banking on a railway track. Both sides were overhung with long grass interspersed with nettles and rosebay willow-herb.

The intensity of the signal showed that they were dead on course for the tracking device.

Angel frowned as the car rocked and splashed through a puddle on the uneven track. ‘Up here?’ he said.

‘We are very close, sir.’

‘Can’t see anything but grass and weeds.’

Angel suddenly had to take a bend round to the right and came onto an open piece of rough ground hardened with clinker from burnt-out coal fires and big enough for a vehicle to turn round. He pulled up in front of a sign. It read: ‘KEEP OUT. Private Property. Employees Grock’s Rhubarb Limited only’.

He read the sign and rubbed his chin.

Behind the sign was a large padlocked gate and beyond that a large spread of low buildings, thirty or more, built close together, in total extending to the size of a football pitch. They appeared to be mainly constructed from corrugated metal sheets and timber, arched like miniature airplane hangars, eight feet tall at the highest point. They had been heavily repaired and patched with all kinds of oddments, sides of packing cases, tea chests, bed heads, tin advertising signs for Mazawattee Tea, Senior Service and Zubes. The structures were roughly weatherproofed with brattice-cloth and heavily daubed with a mixture of tar and creosote. There were no windows and each building had large double doors with a padlock securing it. The place seemed deserted.

Angel looked around and pursed his lips.

‘Ah. They’re rhubarb forcing sheds,’ he said.

‘It doesn’t seem the likely HQ for an armed gang, sir?’

He nodded in agreement and looked across at the monitor. It showed that they were dead on target. ‘This thing is accurate to about forty yards. That car must be in one of these sheds, Ron.’

‘Which one?’

Angel shrugged and got out of the car. ‘There’s nobody about. Let’s take a look round.’

The sign indicated that they had reached a dead end so far as vehicles were concerned. Angel looked through the wooden spars of the gate. There was no sign of anybody. As he turned away, he spotted a trodden pathway between the fence and a hawthorn hedge.

‘Let’s see where this leads,’ Angel said.

They made their way along it for about twenty yards to another hedge with a stile through it. They looked over the stile into a small clearing with an imposing country house ahead, and a barn on the right of it. There was a formal drive up to the house from the left. Angel reckoned that the drive to the house and barn must be accessible from somewhere on the main Bromersley to Huddersfield Road.

Gawber made to climb the stile.

Angel suddenly grabbed the sleeve of his coat. ‘Hang on, Ron,’ he whispered urgently and pulled him behind the hawthorn hedge. ‘There’s somebody coming out of the house.’

Sure enough, from behind the hedge they saw a huge man in a black T-shirt, jeans, trainers and the distinctive jockey cap worn the wrong way. He appeared on the front doorstep of the house. He looked round, then went back in and returned with a slim, young man in a suit. The young man’s head was hanging down, his hands appeared to be tied behind his back. The big man frog-marched him down the steps and across the drive to the barn. The big door was open and fastened back. They went inside.

Angel’s pulse began to race.

Gawber and Angel exchanged glances.

‘There’s one of them,’ Angel whispered. ‘Did you recognize the other man?’

Gawber shook his head.

This was an important discovery. It looked as if they had found the headquarters of the armed gang who had raided Harrison’s flat the previous night. This journey was proving very profitable.

Angel reached into his pocket for his mobile and dialled a number.

‘Keep an eye out. I’ll get some back-up.’

Eventually he got through to his old friend Waldo White. He was the Detective Inspector in charge of the Firearms Support Unit at Wakefield. After they had exchanged pleasantries, Angel put him in the picture and told him their location.

‘There are four men, at least, in the gang, and they are all armed. A head-on confrontation would result in the exchange of fire. I want to avoid that.’

Angel explained that they were up the cart track and at the entrance to Grock’s Rhubarb forcing sheds. They agreed to meet there.

White said: ‘We’ll come straightaway.’

Angel closed down his phone and was about to drop it into his pocket when they suddenly heard a loud and disagreeable voice just behind them say, ‘What are you doing here? Don’t you know you’re trespassing?’

They looked round to see a tall, slim man with heavy five o’clock shadow. He was pointing a hand gun at them.

Angel could see it was a Walther PPK/S. Deadly and accurate from twenty or thirty feet. Angel’s and Gawber’s hearts started thumping.

Angel’s recognized him as another member of the gang. His heart leapt. For a moment, he couldn’t speak. He had a natural aversion to firearms … especially when they were in the hands of somebody else and were being pointed directly at him. He still had the mobile in his hand. He opened his fingers and deliberately let it fall to the ground. It landed silently in a tuft of grass. He hoped that that it might be discovered by Waldo White and that he might realize he had been there.

‘Put your hands up,’ the man growled. ‘I’ve had a good look at your car, so I know you’re coppers.’

‘What’s the gun for?’ Angel said.

‘Shut up, put your hands up, face your front and get over that stile.’

‘What do you want with us?’ Angel said.

‘Shut up,’ the man said.

He marched them across the field to the barn.

Angel’s mind was working overtime. They were in a fix and he couldn’t see a way out.

The man with the gun directed them into the barn. The young man in a suit whom they had seen being frog-marched from the house, was being tied up by the big man. His hands were being secured behind him in a standing position to a sturdy pole, one of four, which supported the barn roof. The young man stared across at Angel and Gawber with glazed eyes but without any emotion. His pasty face had grey patches under the eyes. Angel knew he had been drugged. He thought he had seen a photograph of him recently, but he couldn’t quite place him.

The thug finished tying the man up and turned round as he heard their footsteps. His eyes opened up like bus headlights being switched on. His jaw dropped. ‘Who are they?’ he growled.