ONE WEEK EARLIER

The young woman stood and stretched her arms. After hours sitting hunched up in a dark and damp corner, she was eager to get moving. Her targets were leaving the apartment and she wasn't going to be left behind. Two weeks of careful watching, waiting and following and it was all going to pay off. Soon she would have disposed of them. Soon the Angel Squad would triumph. Soon those pesky brats would be gone for good.

'Hang on,' Amber said. She had been walking down the footpath with Alex, Hex and Paulo but now she stopped with a frown. 'Can anyone remember if I locked the door?'

Hex gave a tired sigh. 'One simple little thing you had to do and-'

'Shut up,' Amber called over her shoulder as she walked back to the apartment.

Trying the handle, Amber found it was locked. She still felt like she'd forgotten something and lingered by the door.

'Hurry up!' Alex and Hex were making their way back to Amber with Paulo trailing along behind.

'Coming,' Amber replied, but she still didn't move. With one last test of the door, Amber started to turn around, preparing to rejoin her friends. Out of the corner of her eye, a shadowy figure stood up. Maybe it was the cautious yet purposeful may the figure moved; maybe it was the fact that they were hiding in an alleyway. Whatever the reason, Amber immediately felt the cold hand of fear grip her heart in a vice.

'Get Paulo,' hissed Amber as Hex ands Alex drew level with her.

Hex looked puzzled. 'What?'

In answer, Amber looked slightly in the direction of the figure. Hex, trusting Amber's judgement, didn't even look, just said, 'What do we do?'

'We walk calmly away. We'll go into Regent's Park and try to lose them there. Whatever happens, we don't split up.' Amber beckoned to Paulo who strolled over, looking slightly puzzled. After the situation was explained to him, the four of them set off the way they had started, taking a leisurely and carefree pace.

They walked around the edge of Regent's Park, painfully aware of the person following them. She was a young woman, dressed in black jeans and a black skivvy. Although her build was slight, she looked strong and controlled, trailing Alpha Force with an easy manner. Halfway down Marylebone Road, Amber spotted York Gate.

'Into the park,' murmured Amber, nudging Paulo. He swung to the right, picking up the pace as the woman behind them lengthened her stride, decreasing the distance between them by several metres.

She'd figured out where they were going and she didn't like it.

Walking up the path, Hex became aware of how quiet it was. The weather was miserable with huge black clouds hanging ominously low overhead, a cold wind blowing and a fine drizzle constantly present. There were a few people scattered around, but they all hurrying through the park, intent on their own business and not aware of the trouble the four teenagers were in.

'Do we run?' Alex whispered as they reached the park's centre.

Paulo cast a casual glance over his shoulder and whipped back around in shock. 'She's right behind us.'

The woman had closed the gap and was striding along two metres behind Alpha Force, grey eyes flat and face expressionless. She was obviously supremely fit, barely breaking a sweat even after her continual fast pace. With the woman gaining on them with every second, Alpha Force knew they had only one option. Without even consulting each other, the four of them simultaneously broke into a steady jog, listening for the quicker footfalls of their follower.

Cutting to the right, across the park, Hex checked behind them, expecting to see the woman right behind them.

'She's gone,' he said flatly and with obvious suspicion. His friends slowed but he shook his head. 'Keep going. Make it look like we were just going for a run.'

Amber scoffed, though she didn't slacken off her pace. 'Yeah, right. She's been watching the house, Hex. Whether we were running from her or just for the hell of it, I doubt it'll make a difference.'

'Just keep running,' Hex grunted.

Gloucester Gate was just ahead of them. Popping out into the street, Amber longed for a coach load of tourists to suddenly pull up, armed with video recorders and cameras. The woman, wherever she'd disappeared to, wouldn't try anything with so many witnesses and so many possible ways to record the evidence. Amber shivered as she realised what she was thinking. Could this woman be the person who had abducted Li? And what was she planning to do to the rest of Alpha Force?

For the next half an hour, they wandered up and down streets, unaware of where they were going, only knowing that they needed to get away from the woman. She reappeared just outside Regent's Park, walking sedately behind them. After that, she vanished and appeared every few minutes. There seemed to be no order, no definite plan that she was following, until Hex realised where they were.

'She's herding us!' he cried, looking in despair at the desolate area surrounding them. It was a no-through road, with no traffic, no people. No witnesses. Warehouses and lock-ups dotted the immediate area.

The woman stepped into the road, feet shoulder-width apart and hands relaxed by her sides. Her stance said that she was in control and she knew it. The teenagers were trapped and no one knew where they were.

'Hello,' she said in a silky voice. 'No hard feelings, but I need to dispose of you four.'

'Dispose?' Hex snorted. 'Why don't you just say murder?'

Beside him, Amber rolled her eyes and sighed inwardly. Trust Hex to not see the obvious life threatening situation breathing in their faces. He'd done it before and he'd do it again.

The woman seemed slightly off put that one of her intended victims answered her back. She was used to people cowering in fear, begging, maybe a bit of swearing, but never the calm, almost disinterested manner that the boy was showing. A frown appeared on the woman's pretty face, but it quickly vanished as she recomposed herself and took a step forward, two long bladed knives appearing in her hands. Twirling them with a lazy grace, the woman took another two steps.

'Knives,' Hex said. 'Clever. No noise, but you'll have to get near us first.'

The woman hissed in annoyance and, with a flick so fast it seemed like her wrist had barely moved, one of the knives twirled out of the woman's hand, flicked a centimetre to the right of Hex and buried itself in a plastic drum half a dozen metres behind Alpha Force. Amber gave a shriek, but Hex didn't even flinch.

'Ah,' he added, still gazing serenely at the woman sent to kill him and his friends. 'Or you could throw the knife.'

'Shut it,' growled the woman, losing her patience as she slipped another knife out of the sheath on her hip. Alex noticed the sheath for the first time and realised that the woman must have put it on when she disappeared in Regent's Park.

'So,' Hex continued, 'what'll it be? Throwing or stabbing?'

'Hex!' snapped Paulo. He lowered his voice so only his friends could hear. 'You are making an already dangerous situation even worse. What are you trying to do?'

Hex smiled. 'Dazzle her with my charms,' he quipped, making Amber scoff. 'I heard that,' he said pointedly, looking at Amber.

The woman hesitated, knives hanging from her hands. What was going on? These four teenagers were laughing and joking, almost as if they had forgotten that she was even there. Even though she had weapons, she felt like she wasn't in control, a fact that bothered her greatly.

It was time to take that control back.

Her training had taught her to find weaknesses and exploit them. In this case, it would work to her advantage to use the tall, dark skinned girl. The others should cooperate better, once they saw her in danger.

The woman gestured so slightly with her head that Alpha Force didn't even register that she had moved. Suddenly, Amber gave a gasp. Hex, Alex and Paulo whirled towards her and took a step back in shock.

'Surprise!' chirped a second woman. She was holding Amber against her, one hand pressing a knife to Amber's throat. The woman gave a bell-like laugh. 'Don't look so shocked to see me. We always hunt in pairs.'

Hex's eyes narrowed. He was angry, worried and confused. Angry because they were partially at fault for getting into this situation. Worried because Amber had a knife jammed against her throat. Confused because he had no idea why they were being targeted. And what had the second woman meant when she said, "We always hunt in pairs"?

Looking at the calm efficiency that the two women were displaying as they backed them into a corner made it click. These women were assassins, sent out to find Alpha Force. And kill them.