Shadows and mysteries. Everyone's afraid of what they can't see. What if there really is something hiding under the bed ? All you have to fear is fear itself.

The lights went out. Oh brilliant ! What else could go wrong ? Dan felt a presence. He couldn't quite put his finger on it, but it didn't feel right. "Tom ?"

"Yeah. One more minute and I'm in," muttered Tom, distractedly.

"Something's not right," said Dan, feeling increasingly nervous.

Tom looked up and stared around him. "I can't see anything," he said, sounding unworried.

"Yeah, well that's possibly because it's dark !" hissed Dan. He started pacing around their position, trying to look in all directions for any possible threat.

"Maybe it's a power cut. It happens," said Tom.

"Have you lost power ?" asked Dan.

"No. The computer network seems to be unaffected," said Tom. "Bingo ! We're in Frank !" said Tom, touching his earpiece.

"Good work Tom ! You're looking for files on the subject of 'Shadows'," prompted Frank.

"Searching now," said Tom staring at his computer screen.

Dan was momentarily distracted by the bright light of Tom's scrolling screen. He dragged his eyes away and continued his pacing, keeping lookout. Worry was gnawing at him. His shoulders were starting to ache from the tension he was storing there. He walked to the far edge of the pool of light cast by Tom's computer screen and stared out into the vast warehouse room they were standing in. Nothing moved. It was silent. He was getting worked up about nothing.

"Found something Frank," said Tom. "Downloading it now." Tom was transmitting files through their comms to Frank directly.

"Tom are you still transmitting ?" asked Frank. "My reception just cut out."

"Yeah, it should still be coming through," said Tom. "Don't worry, it's saved on the laptop," he assured Frank.

Dan had no idea what made him look up. There was a shadowy dark shape on the ceiling. After a split second he registered that it was getting bigger. "Tom ! Run !" shouted Dan. Startled, Tom leapt to his feet and ran a couple of paces before stopping to find out why. That short distance saved him. Dan ran after Tom, but was too late to avoid the falling object. "Agh !" shouted Dan, putting his arms up to protect his head, as a soft, but surprisingly heavy sheet of some kind of fine netting fell on top of him. Dan staggered to his knees as the net wrapped itself around his body. As he tried to push it off, it tightened until he could no longer move his arms. Unable to keep his balance, he toppled over on the floor. The net clung ever tighter as he continued to try to get it off.

"Dan, you need to stop struggling. I think its making it tighter !" warned Tom, watching helplessly as his team-mate was trapped ever tighter in the net. Tom touched the net, trying to work out what it was made of, but where he touched started to cling to his hand. Frightened, he pulled back, touching the metal cabinet he was using as a desk. He pulled his hand free.

Dan saw Tom through the grey veil over his face. "Tom, you need to get out," instructed Dan. "Get the file out. The mission !" he panted. His voice sounded muffled.

"I can't leave you !" said Tom, sounding distressed.

"Dan's right Tom. Get out now. The others will meet you. We'll send a rescue team for Dan," promised Frank.

"But !" complained Tom.

"Tom ! Go !" panted Dan. The net was so tight around his chest he was finding it hard to breathe. He tried staying still. The net finally stopped tightening.

"Tom, leave now ! That's an order," instructed Frank's voice in Tom's ear.

"We won't leave you Dan," whispered Tom, tears in his eyes. He grabbed his computer and ran as if his life depended on it, back the way they had come in.

At the end of the long corridor, he found Aneisha looking anxious. "Tom, come on. We have to go," she said. Tom thought she didn't sound happy either. They both ran for the service lift shaft which they had used to enter the building. Zoe was waiting, with tears in her eyes.

"Tom ?" she asked in a whisper.

"He's alive," said Tom furiously. He stuffed his laptop into his backpack and pulled on the climbing harness. "Come on !" Zoe reminded him how to use the climbing equipment. It had been Dan helping him on the way in, showing him where to put his feet, reminding him how to use the rope and carabiner. Now Dan wasn't there. Tom's anger made the return journey much quicker and easier as he was distracted from his fear of heights by his anger at having to leave Dan. When all three of them emerged, blinking into the evening sunlight, Frank came to meet them, looking worried.

"Right, all three of you in the van," ordered Frank briskly. As they got in, two more larger vans arrived and a SWAT team jumped out. Frank directed them into the building and they all ran in. As the team's van pulled away their last view through the back window was of Frank standing beside the SWAT team vans, holding his mobile phone.

Dan lay in the dark, fighting for every breath. He had never felt more alone in his life. Darkness seemed to be closing in on him. He groaned in pain. Confused and dizzy he heard the softest movement in front of his face. As the blood roared in his ears he felt something touch the net wrapped around his chest. The net loosened only slightly, but it was enough to let him breathe more easily. Chest heaving he sucked in mammoth breaths of air. The red mist over his vision started to clear as something hit him on the back of his head, and he fell unconscious.

Back at base, Tom, Zoe and Aneisha sat together in tense silence. Stella had met them when they arrived and accompanied them down in the lift. Tom wondered briefly why the lift didn't change Stella's clothes like it did theirs. Maybe that was her uniform.

The brief respite from his worries wasn't enough. "Take a seat team," instructed Stella, in her brisk, no-nonsense voice. Her phone rang. "Frank ? Yes. Yes, I understand. I'll let them know," she said. The three teens stared at her intently, waiting desperately for news. "We have Dan," said Stella. The breath they all let go was audible in the silent room. "The SWAT team found him unconscious. There was no sign of the net which trapped him. They're taking him to medical now," explained Stella. They all leapt to their feet. "I expect you want to go," she said. It wasn't a question, more a statement of fact. They nodded. Sighing, Stella pulled a set of keys out of her pocket. "Come on then," she said.

At the MI9 medical centre, Frank was talking to one of the doctors. The doctor explained how they had found a number of bruises around Dan's chest. "His breathing would have been quite constrained at some point," explained the doctor.

"And the concussion ?" asked Frank.

"Blow to the back of the head. He should be coming round soon," promised the doctor. "We'll keep him in for observation, but I don't foresee any problems."

Frank went into Dan's room. Dan lay unconscious in a bed, wearing a plain blue hospital gown. Frank took a chair and prepared to wait. After only a minute or two Dan started to stir. Frank leapt up and called in the doctor. Dan groaned and began to become agitated. The doctor put his head round the door and shortly two male nurses arrived. Only semi-conscious, Dan started pulling at the bed sheets and trying to push them off himself. He pushed the doctor's shoulder away. The two nurses took hold of each of Dan's wrists and shoulders and gently, but firmly, restrained him. The doctor motioned Frank forward. "Can you try to reassure him please Agent London," asked the doctor. "Patients with concussion can become quite agitated. I'm loathe to sedate him at this point, but agents can be surprisingly strong. I've was poleaxed by a woman I thought was completely unconscious once before."

Frank stepped forward and began talking to Dan. "It's alright now Dan. You're safe. You're at the MI9 medical unit. You should stop fighting now. You're free," he promised, speaking gently. "The others are coming. Zoe wants to see you," said Frank. "Just relax for now."

Slowly, Dan calmed and his eyes fluttered open. "Zoe ?" he muttered.

Frank looked at the doctor. "Can she come in ?" Frank asked in a whisper.

"If it helps to keep him calm it would be best," said the doctor. Dan started pulling against the two nurses holding his arms and kicking the blankets. "Yes, now please !" said the doctor. Frank ran out to find the team all sitting outside in the waiting room.