The Vurosis leaned down, its brain glowing fiercely in its socket.

i will grow 'And then what?' The Doctor pursed his lips in thought. 'No, don't tell me: you'll spread out over the whole planet, destroying everything and everyone in your path.'

i will grow and thrive The Doctor turned to Martha. 'There you are, Martha. What did I tell you? The Vurosis is nothing more than a type of weed. Alien, yes.

Virulent, certainly. But at the end of the day just a weed. And it'll do exactly what all weeds do grow, and spread, and choke the life out of everything else around them.'

'So what we need is some weedkiller?'

'Good try, but wrong. This isn't really a plant, or even an animal.

There are no toxins on Earth that could harm it. Left to its own devices, it will extend its roots deeper and deeper into the ground, extending far beyond Creighton Mere, the surrounding villages, Derbyshire, the north of England. . . it will never stop, and nothing will stop it. As it spreads, it will reproduce more versions of itself, which in turn will spread and reproduce as well. Before long, it'll cover the whole of England, then Great Britain. . . '

Martha shook her head. 'No, that can't happen. Somehow they'll find a way to stop it.'

The Doctor raised an eyebrow. '"They"?'

'The authorities. The Government the Army. They'll blast it or burn it or something.'

'Nah.' The Doctor put his hands in his pockets. 'They'll never get it all. It'll spread too deep, too far. And if there's even a bit of it left alive, it'll find a way to grow. That's what the Vurosis does survives, grows, spreads, kills.' Now the Doctor looked directly at her. 'If we're going to stop it, it's got to be here, now, while it's still vulnerable.'

'While it's building its protective barrier?' 'Yeah.' The Doctor turned on his heel and looked at the th.o.r.n.y growth. He lowered his voice. 'But what's it protecting itself from?'

'And why hasn't it zapped us into dust?'

'Ooh! Oh! That's a good question!' The Doctor's eyes widened as his brain moved up a gear. 'I wonder. . . ' He tailed off and then slapped his forehead. 'I know!'

'What?'

'Look all around you! Look at what it's doing growing stuff, spreading its roots, manufacturing a nice little nest for itself.' The thorns had grown much higher now, curving inwards towards the Vurosis as if forming a huge, tangled dome of brambles over the village green. 'It's been cooped up down the bottom of that well for so long, this is the first chance it's ever had to flex its muscles properly.'

'So?'

'So what does it need for all that sudden, accelerated growth?'

'Energy.'

'Top of the cla.s.s, again! Which means there's no more energy left to trans.m.u.tate us into oblivion. Simply put it's leaving us alone while it concentrates on a more important task!'

Martha nodded. 'And I suppose it's leaving us alone because we don't pose any kind of threat.'

'Martha Jones!' The Doctor gave her an admonishing look. 'Shame on you! Us? Not pose a threat to an alien weed trying to destroy all life on Earth? We can pose a threat to anything if we put our minds to it.'

'How?'

'We put our minds to it.' The Doctor tapped the side of his head energetically. 'That thing can mutate every cell in your body by telekinesis, remember. But it has to keep that mental hold if it wants to maintain the transformation. Duncan changed back to human form as soon as the Vurosis broke the telekinetic link. That's its weakness!'

'Weakness?'

The Doctor straightened up, turning to face the Vurosis and squaring his shoulders. 'Hey, you! Weed! I want a word with you.'

do not interrupt the nesting 'Sorry, this is important. Small matter of life and death. This planet's life and your death.' 'Sorry, this is important. Small matter of life and death. This planet's life and your death.'

if you persist i will destroy you 'What? Really?' The Doctor scoffed. 'Use your telekinetic power to warp every cell in my body into your shape? I doubt it!'

i will destroy you 'No way! You couldn't trans.m.u.tate your way out of a paper bag!'

'Doctor. . . ' warned Martha.

But it was too late. With a savage hiss, the Vurosis opened its circular maw and exposed the glowing brain within. Before she could do anything, Martha saw the flash of green light spitting out towards the Doctor. A yell of anguish built inside her throat as the emerald spark connected with the Doctor's forehead.

'Won't. . . work on me,' he gasped. His voice sounded strained and he was already being forced to his knees as the Vurosis energy bore down on him. 'My mind is stronger. . . than a human's,' the Doctor groaned. 'You. . . can't. . . bend. . . it. . . so. . . easily. . . '

But it could. The Doctor sagged beneath the onslaught of the green ray, his face contorted in agony. Martha knew then without any doubt that the Doctor had seriously underestimated the power of the Vurosis. His head snapped up, twisting around until his eyes stared straight into hers, full of pain and fear.

And then the change began. As she watched, almost overcome by panic and anger, Martha saw the veins in the Doctor's head and face bulge and rise up, whitening, about to break out like wires through the skin.

Martha felt herself paralysed, almost faint with fear.

The Doctor's hand stretched up towards her, the fingers already beginning to twist out of shape.[image]

Angela sat at the wheel of her Land-Rover and cursed loudly.

If Gaskin was shocked by such colourful language, he didn't show it. His attention was focused on the strange wall of brambles that had grown, like something from a fairy tale, right around the village green.

The stems were wire-thin, barbed with long, vicious thorns, curving up towards the night sky over the well.

It was a surreal vision. The street lights outside the Drinking Hole cast an unearthly glow over the spiky dome, making it look like a vast, alien pustule on the face of the Earth. The brambles or whatever they actually were were still growing as they watched, extruding from the ground beneath their feet, bending and weaving themselves together to form an impenetrable barrier.

Villagers had gathered around the dome, although almost all of them were keeping their distance. Many were talking on mobile phones or taking pictures. Someone ran out of the pub to say that the police had been called, along with the ambulance service and the fire brigade.

'Might as well call in the Marines as well,' muttered Gaskin.

'What do you mean?' 'They won't get here in time. The Doctor and Martha are inside that thing trapped. They could be dead already for all we know.'

Duncan leaned forward between the front seats. His face was pale and haggard, but otherwise back to normal. 'But we don't know,' he said. 'They could still be alive.'

'What can we do, though?' Gaskin asked, gesturing impatiently at the forest of thorns. 'Look at that thing! It's the perfect barrier.'

'It wants to keep us out, then,' Duncan said.

'You know,' said Angela, her eyes narrowing, 'I really don't feel like doing anything that thing wants, do you?'

'What on earth do you mean?' asked Gaskin.

'Well, as Duncan says. . . it clearly wants to keep us out. I don't think we should give it that satisfaction, do you?'

'I don't think there's much we can do about it.'

'Really?'

She straightened her bush hat and then turned the key in the igni-tion. The Land-Rover rumbled into life.

'Where are you going?' Gaskin asked.

'I'm going to see why it's so keen to keep us out.'

She put the Land-Rover into gear, turned the wheels towards the thorns and then put her foot down.

Automatically, Martha grasped the Doctor's outstretched hand.

His fingers felt hard and bony, but they grabbed hold of her hand and squeezed. It was all she needed. Somewhere inside, the Doctor was reached out to her not just physically, but mentally. He needed her.

He needed her to do something do something.

She forced herself to look into his eyes. They were bloodshot, wide with pain, but inside them the Doctor's intelligence still burned fiercely. It wasn't the insane stare of someone driven beyond their ability to think or act. It was a look that implored her to help.

And then, in a flash, she saw it.

The Vurosis was trying to force the Doctor to change, to mutate so fast that his molecular structure ignited and blew itself into dust. Just like it had with Barney Hackett, and Ben Seddon, and Nigel Carson.

But the Doctor was resisting it.

His body was palpitating, rippling before her eyes as the cells within twisted and turned, but he was holding the damage at bay.

But now he was asking her to help. He couldn't do it alone.

She held his hand tightly in both of hers, as tightly as she could manage, and nodded. Then she looked up at the Vurosis, and the flickering green diamond of its brain.

Martha closed her eyes. She let the green glow envelop her, felt the first tendrils of power sneaking into her mind, alien and cold and malignant.

It was strong. She sensed its power and intention. She sensed the way in which it tried to change her, to dominate her. She even felt it when her body began to change and mutate, causing her to panic and almost let go of the Doctor's hand. Her veins seemed to fill with something other than her blood, something that was as cold as ice and yet burning in its intensity. It was as if a sudden floodgate had been opened deep inside her, precipitating a ma.s.sive and comprehensive transformation that she could not control.

But the Doctor's hand kept its grip on hers, and his mind was there too, somewhere, because she could sense him as well as the Vurosis.

'Concentrate, Martha! Keep holding it back!'

you will not stop me Martha let out an involuntary cry, whether it was pain or fear she wasn't sure. 'I can't. . . It's too powerful. . . '

The Doctor's voice again, clear in her head: 'Yes, you can. You can halt the transformation. Reverse it! Sadie's was halted, remember.

Duncan's was reversed. We can do it!'

The Vurosis renewed its attack and Martha felt the change sweep-ing through her system, literally sensed the veins beneath her skin beginning to respond to its telekinetic effort.

you will not stop me 'I can't do it, Doctor! It's too strong!'

'You must! Together we must!'

YOU WILL NOT STOP ME The searing heat of the trans.m.u.tation overtook her. Martha felt something burning deep within her, at the very core of her being, transforming everything that was human. Her eyes opened, slowly, agonisingly, and in the milky blur of her vision she saw the Doctor. The searing heat of the trans.m.u.tation overtook her. Martha felt something burning deep within her, at the very core of her being, transforming everything that was human. Her eyes opened, slowly, agonisingly, and in the milky blur of her vision she saw the Doctor.

Or what had once been the Doctor.

Now there was a ma.s.s of writhing white weed surrounding his wide, brown eyes, the lips drawn back from his teeth in a feral cry.

The Land-Rover punched right through the thorn barrier, ripping the long wire-like stems apart. The thorns scratched at the vehicle, almost as if they were reacting to its intrusion and were determined to stop it. They dug deep into the metal hide of the car, forcing a series of screeching protests from the old, worn bodywork. The engine roared and the wheels clawed at the ground, churning into the white weed.

Angela kept her foot hard down on the throttle and dropped down a gear, forcing the engine into a metallic shriek. Her knuckles were bone-white on the steering wheel as the veteran Land-Rover bucked and rattled under her grip.

'Keep going!' bellowed Gaskin. 'We're getting through!'

He was holding on to the dashboard, willing the machine on. The Land-Rover reared and then surged forward, the last of the brambles sc.r.a.ping the dark green paint off in strips.

But it was free.

'Ha!' barked Angela gleefully. 'Take that, you blasted alien mon-strosity! This isn't just Earth you're trying to invade. It's England!'

The Land-Rover slewed around as it skidded on the weed, narrowly avoiding the large, gnarled growth containing the barmaid Lucy. Angela swung the wheel and the Land-Rover turned, tipping onto two wheels before crashing back down and speeding towards the well.

It was an eerie, twilight world of pale, alien weed. It was almost like a giant snow globe containing the well and the monster squeezing itself out of it like an enormous worm.

And in front of it, lit by a halo of putrescent green light, were the Doctor and Martha.

'They're still alive!' Duncan said, pointing. 'Are you sure?' Gaskin asked as the Land-Rover came to a stop.

Without thinking, he was already opening the pa.s.senger door to step outside.

Angela had climbed down from the driver's seat. 'Of course he's sure! Look!'

Martha and the Doctor were crouched in front of the Vurosis, hands clasped together. The Doctor was clearly in a bad way, but he still looked up at Angela as she approached. His eyes looked white and cold. 'Trying to. . . hold it back. . . ' he croaked. A pained smile appeared on his lips. 'Could do. . . with a hand. . . '

Angela nodded immediately and said, 'Come on, Henry!'

Gaskin stepped forward a little uncertainly. 'What can we do?'

'Help them, of course!' Angela grabbed hold of Martha's free hand and held out her other hand towards Gaskin.

He reached out and took it. Her hand felt warm and dry in his. She smiled back at him and said, 'It'll be just like making a wish.'

Duncan joined them, looking up in disgust at the Vurosis. 'That thing bullied its way into my mind, made me kill my best friend!' He grabbed hold of Gaskin's other hand. 'Let's do it!'

The Vurosis suddenly twisted and released a ferocious hiss of annoyance. Green light crackled around the well, discharging into the five people gathered around it in a semi-circle.

The Doctor got to his feet, shakily, but the veins were now settling beneath his skin, and his eyes were shining with renewed determina-tion. 'Keep fighting it,' he said. 'It can't change all of us! That's why it was trying to keep you out!'

The green glow of the telekinetic energy flowed over them, winding around their arms and legs, sparking and crackling but unable to settle. There were too many minds to infiltrate at once.

i must grow 'I'm sorry,' the Doctor said. He was looking more like his usual self again, tall, thin, standing up straight as the light flickered over him, his hair moving wildly as the telekinetic force scratched and sc.r.a.ped at his head. He looked directly up at the Vurosis brain, which was now shining with a desperate, blinding green light. Then the electrical storm of energy surged up and around the well, up the Vurosis itself, concentrating on the brain. Long, jerking fingers of green light stabbed out of the brain, lashing at the humans a.s.sembled around it, but without actually connecting. Instead, the wild arcs of light zig-zagged back towards the creature itself. Suddenly it was illuminated from within, so brightly that its internal organs were visible through the fibrous outer hide.