Cold, stale air filled Jessica’s nostrils as she pulled the door behind her and stepped into the lift. She pressed the button to her left and crouched down; her legs still felt like jelly. The lift jolted as it descended to the basement. Once it stopped, she heaved open the grille.

Becky would never believe Jessica if she told her about the bunker. The walls and ceilings were lined with titanium-aluminium alloy, which was bullet- and bombproof. The house could come under mortar attack but it’d still be safe down here. Her dad even stored enough food and water for a week.

She flicked a switch and a computer suite was flooded with light. She looked about. This wasn’t how she’d left it last night. She’d made sure everything was exactly as she’d found it when she’d borrowed the iPad; Dad would kill her if he thought she was using his equipment unsupervised. Files marked “MI6 confidential” were strewn over the floor. She knelt down and flicked one open. It contained the names of MI6 agents in Algeria. Another file listed French agents and a third was marked “Vectra”. It contained a grainy photo of a dark-haired man, wearing sunglasses.

She pulled out her mobile and quickly rang her dad but it went straight to voicemail again.

Now what should she do?

This was seriously freaking bad news. The intruder must have been looking for MI6 agents, but what was Dad doing with their files after all this time anyway? They were dated this year. She looked around the room. On the right-hand side were the cupboards where he kept his equipment from his MI6 days, along with new purchases she secretly borrowed whenever he was away. She pulled open the drawers containing pens, key rings and hand-held games consoles – all hiding surveillance bugs. They were untouched, together with the equipment for picking locks and bugging phones. The intruder wasn’t interested in a stack of fake driving licences and passports either.

Jessica stared at the ranks of computers and television screens. Her dad used the computer on the far side for monitoring tracking devices. It could trace where a person was anywhere in the world. A second computer identified and sifted through voice patterns. It was so sophisticated, it could get rid of all the background noise in a busy bar and pick up the words of a target who was whispering something in someone’s ear. Both computers were turned off. She checked the CCTV equipment. Interior and exterior shots for the last month had been totally erased. The intruder hadn’t taken any chances.

She flopped down in the chair in front of her dad’s main computer. This was bad. Really, really bad. A green light flickered on the side of the black screen. It was already switched on. She tapped the keyboard and her dad’s files appeared, scrolling down the screen. Whoever had broken in was an exceptionally good hacker. Dad never took chances with his work computer, unlike his iPad. Even she didn’t know how to get in. It was protected with a series of encrypted passwords, but the intruder had still managed to access his secret files.

She flicked through the open documents. They were all about someone called Sam Bishop. One was a photo file containing pictures of a man in his thirties. He had bright blue eyes and dark hair. He appeared to be staring into direct sunlight, his hand shielding his right eye. In another, he was standing with his arm thrown around a grey-haired woman’s shoulder.

She clicked open a letter her dad had scanned into the computer. It was from Mrs Bishop, of 33 Crabtree Gardens, Hastings, dated 6th January. It read:

Dear Mr Cole

I have given much consideration to our telephone conversation and decided that I do wish to employ you to find Sam. My fears for his safety grow by the day and I feel I have nowhere left to turn.

As we discussed, Sam was sacked from Allegra Knight Skincare Company, based in Paris, last October after he allegedly failed a random drug test. He was also accused of stealing items from the company. The French police believe he’s gone on the run in Europe to escape prosecution, as he’s made no attempt to re-enter the United Kingdom or get in touch with friends and family.

I refuse to believe this explanation and remain convinced the French police are involved in a cover-up. My son has been anti-drugs since he saw the impact of cannabis use on a few of his former school friends. I do not believe he is taking drugs.

I admit he seemed unhappy the last time we spoke. He wouldn’t tell me what was bothering him but did talk about returning to Cambridge University soon to continue his research.

The company has been in touch to offer its support and to invite me to visit their offices in Paris, but my ill health prevents me from taking up its offer. I would be very grateful if you could visit on my behalf and investigate his disappearance.

Yours sincerely

Louisa Bishop

The final document was a copy of a small local newspaper cutting, dated last November.

MISSING SCIENTIST SPARKS POLICE PROBE

French police are investigating the disappearance of British scientist Sam Bishop, it was revealed yesterday.

The thirty-four-year-old, who was a postgraduate from Cambridge University, was sacked by Allegra Knight Skincare Company (AKSC) on October 30. He has not been seen since.

Local police confirmed they wish to speak to him about the theft of a laptop, confidential lab books and equipment from the company.

Former colleagues in Cambridge say his disappearance is out of character. He had been working as a research scientist at the global beauty firm for six months.

Allegra Knight, founder of AKSC, said: “We are extremely worried about Sam Bishop. Our thoughts are with his family and friends.”

Miss Knight was the first ever “supermodel” in the early 1970s and a muse for every major designer, including Chanel, Givenchy, Valentino and Christian Dior.

She retired from modelling in the 1980s and disappeared from public life before launching AKSC five years ago.

Jessica reread the newspaper article and clicked back to the photograph, intrigued. Why was the intruder interested in you, Sam?

The young man smiled back enigmatically, refusing to give up his secrets. She decided to take a copy of everything to show her dad what had been accessed and hit “print”. As she closed the files, her eyes were drawn to a tiny thumbnail folder at the bottom of the screen. She clicked on to it and waited for it to open. That was odd. The file had no date. It just existed, which was impossible. It must have come from somewhere. Encrypted pages suddenly appeared on the screen – random numbers and letters, apart from the words Sam Bishop and Starfish, which stood out.

She plugged her dad’s external scanner into the computer and did a more detailed search on its origins. She tapped her fingernails on the desk, or what was left of them. They were bitten down and one had started to bleed. She hadn’t realized she’d picked it. She jumped as she heard a noise. Was that the lift? She half-expected the intruder to jump out again, but it was just the central heating coming on upstairs.

Calm down, Jessica.

The info flashed up on the device. The file had been uploaded today at 12.32 p.m., the time of the break-in. She stared back at the computer screen, stunned. Had the intruder planted this on her dad’s hard drive? Why would they do that?

She tried to click open the toolbar but the mouse wasn’t working. She jiggled it about, back and forth, but nothing happened. Suddenly, the cursor moved across the computer screen even though she wasn’t touching the mouse any more. It clicked on the top right-hand corner and closed the file. Someone had taken over control of the computer. She tried to move the mouse again but the cursor hit the “shut down” command and the computer logged off. She flopped back in her chair.

Ohmigod.

Someone had got into her dad’s computer. They must have been alerted as soon as she logged on and somehow piggybacked their way into the programme without her noticing.

Someone, somewhere, was watching her every move.