James checked things were still calm inside Trey's VW, before using a bus tracker app on his phone to work out when Oli would likely arrive. The app said seven minutes to wait when Oli and Daniel came out the back of the supermarket.

'What's back here?' Oli asked, clearly having second thoughts.

Ten metres away, Trey was emerging from the VW. Oli tried doubling back inside the supermarket the instant he saw.

'You get over here,' Trey roared, as Daniel grabbed Oli by the back of his coat, then got an arm around his chest and started marching him.

'Let go you p.r.i.c.k,' Oli shouted, backpack sliding down his arm. 'You don't know what you're doing.'

'I know you ripped us off,' Daniel growled. 'And you lied about doing the print shop for Trey.'

After a few stumbled paces, Oli got shoved to Trey, who dragged him into the car.

'Door,' Trey ordered, as Daniel stumbled in.

The driver moved off, with the VW protesting against the half-closed sliding door with bing-bong sounds. Once he'd slammed it shut, Daniel got back on the rear bench next to Leon. Oli tried to get between them but Trey shoved him face down in the half-metre gap between front and rear seats, then pinned him under a rigger boot.

'You think I wouldn't realise it was you that stole the key?' Trey shouted. 'I've been good to you, Oliver. Gave you jobs when others said you were too young to be trusted. And this is how you repay me?'

Trey had one boot on Oli's back, and used the other one to deliver a kick to the side of his head. Not full strength, but enough to make him gasp.

'You lack respect,' Trey roared. 'Messed up big time.'

Back in the Focus, James felt his heart speed up as he started the engine. He didn't want to stay back too far, but Leon and Daniel's phones were trackable, so losing sight of the VW wouldn't be a calamity.

A Fiat coming in blocked James for a bit, then a man with a buggy crossing the street. Leon's tracker signal seemed to have stopped moving. James guessed it was a traffic light, but after three hundred metres and a left on to a service road he saw the VW parked on a cobbled driveway, leading up to a tatty little mews building. Trey's thug/driver was just shutting the front door.

As James parked across the street and took a laser microphone out of his surveillance kit, so that he'd be able to listen in, Trey shoved Oli against a chewed-up woodwork bench inside.

'See this vice?' Trey shouted, holding Oli's head right up to it. 'One lie, one smart word and I'm gonna use that to crush every bone in your hand. Understand?'

The twins watched, breathing a touch of sawdust and looking around at a big table saw, a lathe and a bunch of other woodworking equipment. Rusted paint cans and partially completed window frames gave the impression that n.o.body had worked here in some time.

'Where are the laptops?' Trey demanded.

Oli looked scared, but shrugged like he wasn't. 'Sold 'em.'

'To whom?'

'That's for me to know,' Oli said.

Trey grabbed Oli by the back of his neck, lifted him one-handed and slammed him hard on the workbench. Leon and Daniel couldn't communicate, but both sized the situation up: Trey's driver was big, but they both thought he could be taken down if they surprised him. Trey was trickier because of the gun, but he'd have a hard job getting the gun out quickly while he was manhandling Oli.

'You wanna mess with me, brat?' Trey roared. 'I'll kill you.'

'If you do, you'll never find your laptops. And what'll Uncle say when he finds out that you let a schoolboy steal a key to his print shop and trash the place?'

Trey tightened Oli's wrist behind his back with one hand, while another grabbed a gas-powered framing stapler from a shelf under the bench.

'Last chance, Oliver.'

'What's on the laptops, Trey?' Oli teased. 'What's Uncle gonna say when he finds out you've lost 'em?'

The gas-powered stapler had a cartridge filled with heavy-duty staples, strong enough to drive through the thin board that you might find as the base of a drawer, or backing a kitchen cabinet. When Trey pulled the trigger, there was a little explosion and a 10mm staple shot into the back of Oli's hand.

'Tell me now or I'll crucify you,' Trey roared.

Oli screamed in pain as Trey lined up the stapler to take another shot.

'Nooo,' Oli begged, tears streaming down his face. 'There's a p.a.w.nbroker's.'

'Where?'

'Booth Street, near the station.'

Trey turned towards his driver. 'Look it up. See if we can get there before it closes.'

'How dare you rip me off?' Trey roared, his attention back on Oli.

Trey fired a second staple into the back of Oli's hand. As the twelve-year-old screamed, Leon saw that the driver was focused entirely on Googling with his phone. He glanced at Daniel, who made a slight nod towards Trey.

'Gotcha,' Leon murmured.

Leon launched himself at the driver, using a pivoting high kick that caught him in the temple and knocked him cold. As the big man crashed, Daniel grabbed a length of wood resting against a wall and made a lance, driving it hard into Trey's stomach.

As Trey gasped, Daniel felled him with a kick behind the knee and ripped the stapler out of his hands. CHERUB agents are trained to use minimum force, but Daniel didn't have much time for people who fire staples into twelve-year-olds. Even if the twelve-year-old in question was a horrible lying s.h.i.t ...

'See how you like it,' Daniel roared, as he put the stapler against Trey's b.u.t.t and fired three staples through his jeans.

'Dude!' Leon said, jangling the keys to the VW as he gave Daniel a shove. 'We're in enough trouble already.'

Daniel knew his brother was right, so instead of shooting another staple, he swung a punch with the tool, catching Trey in the head and knocking him cold. Then he crouched down and took the pocket revolver, instinctively checking inside the barrel before dropping it into his front tracksuit pocket.

'One measly bullet,' Daniel noted, showing his brother.

Oli had been bawling his head off the whole time and as the twins closed in, they realised that while one staple hadn't done much damage, the second was lodged deep in the bony part of his index finger.

'Gruesome,' Leon said.

On some level, both twins felt sorry for Oli. For all his faults, Oli was a mixed-up kid who'd had tough breaks. But they had to stay in character for the sake of the mission, and Oli had lied and cheated them.

'Where's the money you made today?' Leon demanded.

Oli had tears streaming down his face. 'In my shorts,' he sobbed.

It took Leon a couple of seconds to work this out, but when he lifted Oli's jacket, he realised that Oli wore shorts with pockets under his jeans.

'Money's ours,' Leon said, as he ripped open a Velcro pocket and pulled out several hundred pounds in twenties.

'All of it,' Daniel added.

'Please,' Oli sniffled.

'There's six hundred quid here,' Leon said brightly. 'Any complaints?'

Oli flickered with anger, then sighed. 'It's yours. I'm sorry. OK?'

Across the room, Trey's driver was coming around and making a move towards the door.

'One more move,' Leon warned, brandishing the stapler and making his point with a couple of shots at the ceiling.

Oli groaned as Daniel helped him off the table.

'Suppose we'd better take you to hospital,' Daniel said, as he tore white tissue out of a dispenser. 'Wrap this around your hand.'

'I'll drive,' Leon added, rattling the keys to the Volkswagen.

17. p.a.w.n.

Freja was a Dane by birth: witchlike grey hair and somewhere in her early sixties. She moved like she was younger as she opened the door of her small shop. It was in a side road, close to Birmingham New Street station, and a customer in a suit wanted to get in as she stepped out, carrying a freestanding sign that read, We Buy Gold for .

The customer wanted a watch battery. Freja opened dozens of tiny plastic drawers behind the shop counter until she found the right size. She charged four pounds and offered to fit for free, but the man was in a hurry and said he'd do it himself. As she put the day's first takings in the till, Freja heard the bell over the shop door jangle, and saw two large men reflected in a gla.s.s cabinet full of second-hand camera equipment.

'Good morning, gentlemen.'

Trey had spent much of the previous evening in casualty. There was bandage under his tracksuit bottoms where three staples had been removed. His big hands drummed on the counter.

'Kid came in yesterday,' he began. 'Stocky lad. Four MacBook Airs that belong to me. Don't want no fuss, I'll pay back whatever you paid the kid.'

In the background, Trey's driver pulled a roll of fifty-pound notes.

'Six hundred, wasn't it?'

Freja stiffened up, giving the impression that she'd dealt with plenty of situations like this before. At the same moment, the driver bolted the shop door and flipped a sign to closed.

'No laptops or other high-value items are kept on these premises,' Freja said. 'I wasn't working yesterday. But if my colleague purchased a computer, it will have been pa.s.sed on to our reseller. They either strip the equipment for parts or wipe all the data and sell them on eBay.'

'Can you get them back?' Trey asked. 'There's data on those machines that is important to us. I'll even give you an extra two hundred pounds for your trouble.'

Freja smiled slightly at this prospect. 'Let me check.'

The elderly Dane had yet to boot up the ancient Windows PC behind the till.

'You often pay money to kids bunking off school?' Trey said, trying to sound vaguely threatening. 'You're lucky I didn't go to the cops.'

Freja gave a stiff smile, as she logged into the computer and started going through a database of invoices for the previous afternoon.

'I've worked in this store more than a dozen years,' Freja said coyly. 'In my experience, people either go to the police first, or not at all.'

Trey looked sore, but kept fingers drumming and his mouth shut.

'Six hundred pounds, four times thirteen-inch MacBook computers,' Freja finally announced, as she swivelled the monitor so that Trey could see. 'I can call our reseller and see if we can get them back before the data is erased.'

Trey nodded, then looked tense as Freja grabbed an old-fashioned phone with a long curly lead. There was a brief conversation.

'You gentlemen are in luck,' Freja said. 'The equipment takes a couple of days to process. Our reseller can bring the laptops back when they make their collection run this afternoon. Eight hundred pounds will cover what we paid, plus our handling costs. I'd suggest you drop in just before we close at six. Or first thing tomorrow.'

Trey looked frustrated, but was more concerned with speed than with paying an extra two hundred. 'Is there any way we could get them sooner?'

'The reseller is based in Watford,' Freja said. 'If you leave your mobile number, I'd be more than happy to call as soon as they arrive.'

Trey tutted, before jotting his mobile number on a We Buy Gold flyer. Once the big men had left, Freja took the piece of paper into a back room, separated from the rest of the shop by a bead curtain.

Besides a kettle and sandwich toaster, the s.p.a.ce was crammed to the ceiling with junk, from old paperwork to cardboard boxes filled with broken electrical gear and shelves of musical instruments.

There was a tiny desk in the corner, at which James Adams sat with four open MacBooks. Each one was locked and encrypted, so he had the backs off and was using his own laptop to make bit-for-bit copies of the hard drives.

'You handled that really well,' James said warmly.

Freja smiled. 'Twenty-five years in this business. You get used to cops asking questions and guys demanding their stuff back. So how long will it take to copy the hard drives?'

'Couple of hours,' James said.

'Why not just take the laptops?' Freja asked.

James smiled. 'Information tends to be more valuable if the bad guys don't know you've got it.'

'So who are they, Detective?' Freja asked. 'Should I be worried?'

'I'm on to something,' James explained. 'But at this stage, I have no clue what that something is.'

Trey got his laptops back just after 4 p.m. CHERUB's head mission controller, John Jones, arrived in Birmingham ninety minutes later, and met with James, Leon and Daniel around the dining-table in the flat over Morrisons.

'Two sugars,' James said, as he put a chipped World's Best Auntie mug on the table in front of his boss.

'So what was on the laptops?' Leon asked.