“SommeWorld,” muttered Jack. “That’s all we need.” They walked slowly along the perimeter until Mary noticed a gap in the fence. She went and had a closer look as Jack went on ahead.

“Jack, I think you better look at this.”

“It’s probably kids,” he said, retracing his steps, “wanting to have a look at the park before it opens.”

“Look,” said Mary, pointing at a small scrap of cloth stuck on the chain-link fence. “It’s a scrap of blue-patterned dress.”

“Goldilocks wore a dress of that sort,” murmured Jack as they both stared into the silent park. It wouldn’t open for another three months. “Thinking what I’m thinking?”

Mary nodded, and they carefully climbed through the hole and looked around. The pockmarked damage of the shelling began about thirty yards in from the fence. The First World War theme park had been a major news story over the past six years, and the biggest problem the designers faced was to make the park “guests” undergo a two-hour-long artillery barrage, but with zero danger. No one knew how they managed it, but they had been testing for a number of months, and all, apparently, was well. Jack and Mary picked across the freshly tossed earth and came across a large crater with battle debris scattered about and the remains of some barbed wire. The wire was real, and it tore a hole in Jack’s trouser leg. He was just surveying the disjointed landscape and thinking that perhaps Goldilocks was sunning herself on a foreign shore somewhere when Mary reached down and pulled something from the freshly pulverized earth.

“What do you make of that?” she asked.

It was not from the First World War, or even close. It was a small piece of white plastic the size of a Scrabble tile with the letter M printed on one side. But it wasn’t a Scrabble tile. It was a computer key.

“Her laptop?”

“Could be.”

They had both started to search the ground for anything more when there was a loud whompa! noise and a plume of earth shot high in the air less than thirty feet away. They ducked as the soil and debris fell around them and coughed in the cloud of dust that drifted across.

“What was that?” said Mary, rubbing her eyes.

Before Jack could answer, there were two more dull thuds and two more plumes of earth shot skyward, this time with greater force—and closer. The search momentarily forgotten, they dashed for the fence amid a barrage of increasing violence, with earth, roots and small stones cascading down around them.

Jack reached the fence first and threw himself through the gap.

“Well, Mary, that was—”

He stopped. Mary wasn’t with him. He stared back into the barrage, the rising column of soil and the pebbles bouncing on the ground in front of him and the dry dust in the summer heat drifting like a smoke screen, making him blink and hiding the scene from his view. He had run over his previous sergeant with his wife’s Volvo and killed him. It was an accident, of course, but to lose one sergeant is a misfortune. To lose two would be considered…

He was just about to dash back toward the destruction to look for her when a small figure stumbled from the barrage, which even now was beginning to wane. She was covered in dirt, her hair was sticking almost straight up, and she had lost a sleeve off her jacket. She fell to the ground quite out of breath, but with a smile on her face.

“What happened to you?”

“I… saw… this,” said Mary in between breaths. She passed him a large section of broken laptop. “I… thought… it… important!”

Jack turned the casing over. Written on the bottom, in indelible marker, were Goldilocks’s name and phone number.

Jack and Mary drove into the car park at SommeWorld a half hour later and parked in front of the theme park’s buildings. Most of the visitors’ center was finished, but the roof had yet to go on to the auditorium, and the canteen hadn’t even been started. Builders were toiling around the clock in order for the construction to be over by Christmas. That was four months away, but there was still a lot to do. Two years behind schedule and ten years in the planning, the bizarre theme park was the longtime personal dream of the Quangle-Wangle, the reclusive industrialist, computer and shipping billionaire whose own experiences on the Somme had been the basis of what he called “the only safe real-life war experience in the world.”

They parked the car, entered the impressive dome-roofed visitors’ center and were directed up the stairs to the park operations center. They walked along the partially finished corridors until they found the correct door, and Mary pressed the entry buzzer. She stuck an index finger in her ear and waggled it.

“I don’t know how those explosions work, but the concussion is for real. One went off a couple of yards from me, and I felt my ears pop like a champagne cork.”

The door opened to reveal a young man of about twenty with a goatee and matching SommeWorld T-shirt and baseball cap. He looked at them both in turn.

“Can I help you guys?”

“Police,” said Mary. “We want to see whoever’s in charge.”

“Sure,” said the young man, leading them into the spacious control room perched on the upper floors of the visitors’ center.

“What’s this all about? Someone complaining about the noise again?”

Inside the room were a dozen or so Quang-6000 computers with technicians hunched over them, doubtless trying to debug whatever problems with which SommeWorld was beset. In front of the consoles, a large window assured the operators an unimpaired view across the battlefield. As they watched, a flight of low-flying Sopwith Camels buzzed across the smoking battlefield and three separate explosions went off near the ruined church.

“No, no, no,” said the supervisor into a microphone. “We can’t get away with a simulated bombing run unless we actually drop something. Land and we’ll try something else.”

“Mr. Haig?” said Jack and Mary’s guide quite timidly. “The police would like a word.”

Haig looked up and strode over. His manner was abrupt but helpful.

“Good afternoon, Officers.” He caught sight of Mary’s tattered state. “My goodness! What happened to you?”

“I’m DS Mary Mary, head of Reading’s NCD, and this is Inspector Spratt. I want you to shut down the park.”

Haig knew better than to ask why. The park was a legal nightmare over public liability, and everyone had been told to cooperate fully with authority. He turned to the operators. “Code-red shutdown, disarm all air mortars.”