'Whatever the Doctor said was wrong,' interrupted Zalloua briskly.

'He is the one who hasn't the slightest idea of what he is doing. The Xarax must be allowed to carry out the program I gave them.'

'But your program won't work! The Doctor said - '

'That the Xarax can't tell one human from another? That's quite right. But the program I have given to the Xarax in Kebir City doesn't need them to be able to do that.' He paused, smiled. 'I wanted peace, you see. Not just between the Kebiriz and the Giltaz, but for the whole world. But given the nature of humanity, there is only one way to do that. Everything else has been tried.

'I have told the Xarax to make perfect copies of all humanity - and then to use the copies to replace us.' He smiled again. 'Don't you think it's a good idea?'

Twenty-Six.

FThe tank slewed sideways, jolted violently. The Brigadier winced as his injured arm caught against a projecting piece of the gun sight.

'Doctor, do you think you could be - '

His comment was cut off by an extremely loud bang. The tank seemed to lift off the ground for a moment, then settled with another spine-jarring jolt.

'Missed!' said the Doctor, with some satisfaction.

The Brigadier looked at Rashid, who shrugged and pa.s.sed him the radio mike. 'See if you can get Al-Bitar, he's got the ground-to-air missiles.'

The Brigadier looked at his list, found Al-Bitar's call sign.

'Greyhound to trap seventy-one, come in.'

Silence.

'Trap seventy-one, come in please.'

'h.e.l.lo this is Lt Tanzi,' said a weak voice. 'Al-Bitar's had it, sir.'

There was another explosion, and the voice on the radio cried out.

The Brigadier came to a decision. 'I'm going up to take a look,' he said.

'Be careful, Brigadier,' said the Doctor and Rashid, almost simultaneously. The Brigadier grabbed a stanchion with his good arm, levered open the hatch and stepped up.

Heat, light and grit hit his face all at once. For a moment he was half-blinded, then he saw a blue sky streaked with smoke trails, the flash of a Xarax carapace in the sunlight. He looked back along the column, strung out along a rough trail which descended between high banks of red scree. He could see Al-Bitar's detachment dimly through a curtain of dust and smoke. Somebody was still firing something - a medium-calibre gun by the look of it - but at what, and with what degree of success, the Brigadier couldn't tell.

Abruptly the tank lurched sideways, and a wall of rock cut off the Brigadier's view of the action. He ducked down again, asked, 'Where are we going now?'

The Doctor didn't take his eyes from the forward scope. 'Short cut, Brigadier.' The tank lurched downwards, almost throwing the Brigadier off the ladder. The treads skidded for a moment on loose pebbles, then they got a grip. 'I suggest you get inside,' said the Doctor.

The Brigadier ignored him, looked out of the hatch again. Ahead there was something that looked perilously like a sheer drop.

'Doctor! I hope you know what you're doing!' he shouted.

'Of course I do, Brigadier!'

The tank nosed its way on to a ledge about a foot wider than it was, and started down the ravine at an angle the Brigadier didn't care to think about. He stayed just long enough to see the next tank in the column starting to follow them down. Then he got inside and slammed the hatch.

'How short, exactly, is this "short cut", Doctor?' he asked.

'It's only about ninety kilometres to the border from here. We should make it in a couple of hours.'

There was a loud thud from outside the tank, followed after a brief interval by the sound of a fair amount of rock clattering down on the armour.

'With a bit of luck, that is,' added the Doctor.

Benton wasn't sure how he'd reached the lawns. He remembered running, firing, a bullet shattering the plaster of a wall inches from his ear as he ran up the back steps.

Now he was in the clear. There was a rattle of gunfire still coming from the house; as he watched, two of the lads - Pepworth and Morgan - staggered up the steps and crossed the flagstoned path that ran around the rear of the HQ building.

Pepworth was hurt, red blood spreading over his combat jacket.

A first floor window shattered above them, gunfire sprayed down.

Benton hit the gra.s.s, rolled into the cover of a hedge. He saw Pepworth and Morgan drop, saw their bodies jerk as the bullets. .h.i.t them.

Swore.

The firing from above stopped abruptly. Gla.s.s shattered again, and a rain of fragments landed on the path, followed by something heavier.

A body.

No. The body of an alien. Benton could see the honey-like fluid flowing out of the cracks in the chest.

But the alien was still moving, bringing its gun to bear -

Benton rolled out of the way just in time, stood up, watched as the damaged creature went on firing into the hedge until the gun overheated and jammed.

He looked up, saw the face of Corporal Cranley in the window.

The Corporal grinned, waved. Then frowned. Then fell forward through the remains of the window and pitched on to the stone path head first.

Benton raised his gun, waited until he saw something move. Then fired, a continuous burst.

A gun clattered down to the ground, with a hand still attached to it.

The human form in the window continued to crouch and aim, the other hand crooked around the gun that was no longer there.

Benton ran up to Cranley, stopped when he saw the bullet hole in the back of the man's neck.

Swore again.

He stepped across to Pepworth and Morgan, saw Morgan sitting up, cradling his left arm. Bright arterial blood dripped from the cuff of his jacket.

Morgan looked at Benton, shook his head slowly; Benton looked down, saw the line of bullet holes in Pepworth's back. He reached down to turn the man over, stopped when he saw movement in the doorway at the bottom of the steps.

He raised his gun, then saw Corporal Marks's face.

'We seem to have got most of 'em, sergeant,' said Marks as he jogged up the steps. 'At any rate, they've gone.' Then he looked down at Pepworth. 'Oh, blimey.'

A crackle of gunfire from the building made them both jump around to face the doorway, but all they saw was the remainder of the platoon, following Marks out.

Then Benton heard the whistle and thud of a mortar sh.e.l.l and realized that the firing was coming not from within the building but from the other side of it. He glanced at Marks, who was tying a tourniquet around Morgan's injured arm.

'Best if we go round the front and take a look.'

Marks nodded; Morgan said, 'I can walk, sergeant.'

He got up, leaning on Marks. There was another whistle and thud, then Benton heard a scream of pain. He set off at a trot, rounded the side of the house, saw bodies scattered on the driveway.

Bodies in pieces. Bodies leaking a brownish fluid. Bodies that could only be aliens. He saw Huffington's men around the gate, heaved a sigh of relief. Round one to the humans.

Then the mortar thudded, a sh.e.l.l whistled overhead and exploded behind him. The blast almost knocked him off his feet. He glanced over his shoulder, saw the men rolling for cover.

He waved his rifle in the air, shouted, 'It's us! Sergeant Benton's squad!'

But the mortar thudded again, and a crackle of machine-gun fire started up. Benton dived, covered his head.

The explosion shook the ground, left him deafened. He looked up, saw Huffington's men advancing. No.

Not Huffington's men. They moved too quickly.

Too quickly to be human.

'Round one to the aliens, then,' he muttered aloud.

He looked over his shoulder, saw the men running, a body on the ground. He ran up: saw Morgan, his eyes glazed, his mouth slackly open, dribbling blood.

Benton looked back at the advancing aliens, heard the crump of the mortar again.

He ran.

The men were ahead of him, running in disorder across the rear lawn. The mortar sh.e.l.l exploded somewhere to the left of them: they dropped, then scrambled up again, heading for the narrow, one-man gate in the fence at the back of the compound.

The gate was locked. Benton saw them struggling with it, saw Marks take a shot at the lock.

The gate still didn't open.

'Cut the wire!' yelled Benton.

Someone produced a knife, began chopping at the wire of the fence next to the gate. Benton turned, saw the aliens approaching across the lawn, making gra.s.shopper-like leaps. He fired into them, saw one spin out of control, land heavily and break into pieces.

The others kept coming.

'Okay, sarge!' shouted Marks from behind him. Benton turned, saw the men pushing their way through the fence. He took a grenade from his belt, pulled the pin, hurled it over his shoulder without bothering to look. Dived for the gap in the fence.

The grenade went off as he was struggling through. He heard an explosion of gunfire, saw Marks firing through the fence. Ran.

Marks ran with him. 'Where to, sarge?'

'Henley Wood,' said Benton, without hesitation.

Marks nodded. Henley Wood was their training ground; they'd fought more wars there than they were ever likely to fight anywhere in real life. And there was plenty of cover. They should have a chance.

He hoped.

Benton looked over his shoulder, saw that the aliens had stopped, spread out against the fence. For a moment he thought that the barrier had confused them, that they wouldn't find the gap; then he saw the whole high structure topple forward. The aliens started their gra.s.sshopper-leap progress once more.

Ahead, the men were piling over the stile at the fringe of the woods. Benton sprinted to catch up with them.

Undergrowth, he thought. We need undergrowth. We need to hide hide.

He scrambled over the stile, looked around him. A slope covered in scattered beech trees led away to a stream; on the far side of the stream was a green thicket of rhododendrons.

They would do.

'Down the slope!' he shouted.

Now he led the way, reaching the stream, splashing through it, diving for the cover of the thicket. His men crashed down around him. Benton heard gasping breath, smelled sweat, fear.

'Don't fire unless you have to,' he said. 'They don't seem too bright.