You'll pay for this!'

Ruth came to the defence of her colleague. 'The decision was entirely mine, Professor. I take full responsibility for testing the apparatus, and I'm prepared to justify my action at the highest level.

Perhaps we had better go and see the Director and sort all this out before the demonstration.'

With a mighty effort the Master controlled himself. When he spoke, his voice was once calm and reasonable. 'I'm sorry Doctor Ingram, you must excuse me. It will not be necessary to take this matter any further.'

But now Ruth was angry in her turn. 'That's all very well, Professor. After the things you've been saying -'

'Please,' said the Master forcefully. 'Accept my apologies.'

Ruth drew a deep breath. 'Well, perhaps it was a bit unethical of me not to have told you.'

'Come off it, Ruth,' said Stuart. 'He's only climbing down because he needs you for the demonstration.'

'How very clever of you, Mr Hyde,' said the Master smoothly. 'Of course I need you, both of you.'

Stuart couldn't help feeling mollified. 'After all Prof, let's face it, we couldn't risk a foul-up this afternoon, could we?'

'Say no more,' said the Master magnanimously. 'The matter is closed.'

'Well, not quite,' said Ruth a little guiltily. 'You see, it wasn't all plain sailing. We had some sort of positive feedback. There was an overload.'

.'But that's impossible.'

'See for yourself.' She tore off the print-out from the computer and handed it to him.

The Master studied it thoughtfully. 'I see. . . Of course, how foolish of me.'

They heard Stuart calling from the inner lab. 'Hey Ruth, Professor. The crystal - it's still glowing!'

The Master snapped his fingers. 'Of course it is! I see . . .'

Ruth looked dubiously at him. 'You know what caused the overload then?'

'Of course. You must have been drawing some kind of power from outside time itself.

We must build a time vector filter into the transmitter.' The Master s.n.a.t.c.hed up a pencil from the bench, and began drawing on the computer read-out paper. 'Here, let me show you.' With amazing speed, he sketched an elaborate circuit diagram. 'You see? In effect, it's a sort of paracybernetic control circuit.'

Ruth studied the diagram. 'Yes, I See. But won't this take some time to line up? The demonstration is at two.'

'Indeed it will - and I'm afraid I must leave the task to you. I am expected to eat a pretentious lunch .and exchange ba.n.a.lities with our guests.'

Stuart Hyde was an amiable soul and he was happy that a semblance of good feeling had been restored.

'Don't worry, Prof, you go off and enjoy your nosh. Leave it to the toiling ma.s.ses.'

'I have every confidence in you, Mr Hyde.' said the Master smoothly. 'And of course, in you, Doctor Ingram.'

Stuart had wandered over to the window. 'Hey, you'd better get your skates on, Professor. The VIPs are arriving.., escorted by UNIT no less.

'The Master hurried to the window.

An enormous black limousine was gliding up the drive, with an Army landrover close behind it. Gold letters were painted on the side panel of the jeep.

'UNIT,' muttered the Master. 'What are they they doing here?' doing here?'

Stuart shrugged. 'Military observers, I suppose. Happens all the time. The Government are the only people with the money for our sort of nonsense these days.'

The Master turned away from the window: 'Doctor Ingram I have changed my mind. I I shall stay here and set up the time vector filter myself with the a.s.sistance of Mr Hyde, of course.' shall stay here and set up the time vector filter myself with the a.s.sistance of Mr Hyde, of course.'

Ruth gave him an offended look. 'I a.s.sure am perfectly capable of constructing the circuit '

'And I am sure you are equally capable of a eating a tough pheasant on my behalf.'

'But why don't you want to go suddenly?'

The Master's voice was throbbing with sincerity. 'I am a life-long pacifist, Doctor Ingram. The a.s.sociation of the military, with violence, with killing. .'He shuddered delicately. 'Please bear with me.'

Ruth thought the Professor made a most unlikely pacifist, but she had no alternative but to agree. 'Very well I'll get them to send you some sandwiches across.'

'Good thinking, Batman,' said Stuart. As he helped her off with her lab coat he whispered. 'We've got a right nutcase on our hands!'

3.

The Summoning

The occupants of the two vehicles parked outside the Inst.i.tute were staring in astonishment at what looked like a freak accident. They stood in a little semi-circle around the window cleaner who was laying sprawled out and motionless on the gravel drive.

There were four of them in the group: Doctor Cook, chairman of the Grants Committee, a serious, indeed pompous man in his middle fifties; Proctor his a.s.sistant, younger, and nervously deferential; Sergeant Benton, back in uniform and still sighing for his vanished leave; and finally, there was the immaculate figure of Brigadier Lethbridge-Stewart, who was kneeling beside the body and taking its pulse.

'He's not dead, is he?' asked Doctor Cook nervously.

The Brigadier stood up. 'No, he's still breathing.'

'Well - who is he?'

The Brigadier glanced at the ladder still propped up against the building. 'A window cleaner, I presume. Must have fallen off his ladder.' He studied the unconscious but apparently uninjured form. 'It's a miracle he's still alive.'

'Poor fellow,' said Cook indifferently. 'Come along, Proctor. I trust you'll make the necessary arrangements to get the man to hospital, Brigadier?'

The Brigadier too knew all about the advantage of delegation. 'Yes, of course sir, leave it to me He raised his voice. 'Sergeant Benton! See to it will you?'

Bessie, the Doctor's little yellow roadster, shot along the narrow country lane with the Doctor at the wheel. He cut a colourful figure in his elegant burgundy smoking jacket, ruffled shirt and flowing cloak. Beside him sat Jo Grant, a map spread out on her lap, the time sensor resting on top of it. She was wearing a warm fluffy coat over her mini-dress.

She glanced up at the sky which was dull and overcast. 'Isn't it a doomy day? I mean, look at the sky. Just look look at it!' at it!'

The Doctor was concentrating on his driving. 'My dear girl, stop whiffling. We're not out on a pleasure. jaunt.'

'Sorry, Doctor.'

What they were out on, thought Jo, was more of a wild goose chase. The plan was to drive about in a more or less random search pattern, covering the general area from which the mysterious time signal had originated.

The Doctor said, 'If it is the Master, we can't run the risk of losing him. So you just keep your eye on the sensor.'

Obediently Jo glanced at the sensor on her lap and found to her astonishment that its little scanner aerial was whirling frantically.

'Doctor, it's working again!'

The Doctor stopped the car. 'What's the bearing?'

Jo made a rapid calculation. 'Zero seven four. And it's . . .sixteen point thirty-nine miles away.'

'That's Venusian miles. That'd be seventy-two point seventy-eight miles ...' He studied the map. 'Which puts it about - here. A village called Wootton.'

'Wootton? But that's where the Brigadier and Sergeant Benton went to.'

'TOMt.i.t!' said the Doctor. 'If the Master's behind that... What time's the demonstration, Jo?'

'Two o'clock, I think.'

'We've got to stop it!'

The Doctor started the car, and flicked the super-drive switch. Bessie streaked away at an impossibly high speed.

Ruth Ingram was thoroughly relieved when lunch was over at last. It had had been pheasant - tough pheasant - just as the Professor had predicted. been pheasant - tough pheasant - just as the Professor had predicted.

Socially speaking, it had not been the most enjoyable of occasions. Throughout the meal, Doctor Cook had whinged on about the need for stringent economies. Indeed, he was still doing so now as the little group made its way into the TOMt.i.t laboratory.

'Well, that's how it is, Charles. It may seem churlish of me after eating your excellent lunch though how the Inst.i.tute can afford pheasant I really don't know...'

'We are are in the depths of the country,' protested the Director feebly. He had been silent and abstracted throughout the meal as if part of his mind wasn't really with them at all. in the depths of the country,' protested the Director feebly. He had been silent and abstracted throughout the meal as if part of his mind wasn't really with them at all.

Cook strode on into the laboratory. 'Be that as it may, we are responsible for international funds, public money. I.doubt very much whether we should allow ourselves the luxury of either pheasants or or TOMt.i.ts.' He laughed loudly at his own laborious joke, and Proctor t.i.ttered obsequiously. TOMt.i.ts.' He laughed loudly at his own laborious joke, and Proctor t.i.ttered obsequiously.

Ruth looked round the empty laboratory. 'Well, she said awkwardly, 'the Professor doesn't seem to be here.'

'Obviously,' said the Director pettishly. Stuart came from the inner laboratory, suited up except for his helmet, which he carried under arm.

Ruth greeted him with relief. 'There you Stuart. Where's the Professor?'

'Search me. He was here a couple of minutes ago.'

'Who is this fellow Thascalos, anyway?' demanded Cook. 'I've never heard of him.'

The Director seemed to come to life. 'Oh excellent background, excellent,' he said enthusiastically. 'Surely you've read his paper on the granular structure of time?'

'It's all I can do to keep up with my Departmental papers,' said Cook loftily. 'I leave all the rest to Proctor here.'

He glanced sharply at his a.s.sistant, who shook his head apologetically. 'New one on me, sir afraid.'

The Brigadier was gazing around the laboratory which was cluttered with equipment.

'Fearsome looking load of electronic nonsense you've got Doctor Ingram,' he said briskly. 'How does it work - and what does it do?'

Ruth drew a deep breath. 'Well. . . .'

'In words of one syllable, please,' said the Brigadier hurriedly.

Ruth smiled. 'I'll do my best. Now, according to Professor Thascalos's theory, time isn't smooth. It's made up of bits.'

'A series of minute present-moments,' said Stuart helpfully.

Ruth nodded. 'That's it. Temporal atoms, so to speak. So, if one could push something through the interstices between them, it would be outside our s.p.a.ce-time continuum altogether.'

The Brigadier gave her a baffled look. 'Where would it be, then?'

'Nowhere at all, in ordinary terms.'

'You've lost me, Doctor Ingram.'

'And me,' said Humphrey Cook emphatically. 'Never heard such a farrago of unscientific rubbish in my life. It's an impossible concept.'

'But we've done it,' said Stuart triumphantly. 'We shoved a vase through here -' He indicated the transmission platform- 'and brought it back in there.'

And he pointed to the inner laboratory.

'Shoved it through where?' asked the Brigadier exasperatedly.

Benton, who had been standing silent and a little overawed at the back of the group said unexpectedly, 'Through the crack between now and now, sir.'

The Brigadier shook his head. Where was the Doctor when he needed him? 'I give up. It's beyond me.'

A deep, foreign-accented voice said, 'Then you must see for yourselves!'

In the doorway stood a figure in a radiation suit, features obscured by the visored helmet. 'I must apologise for keeping you all waiting. Shall we begin?'

Jo clutched the edge of her seat as Bessie sped along the lanes at a speed, she was sure, of several hundred miles an hour. 'Please slow down, Doctor. It's not safe to drive so quickly.' They were moving so fast that the countryside around them was no more than a blur.

'It's perfectly safe,' shouted the Doctor cheerfully. 'My reactions are ten times as fast as yours remember. And Bessie's no ordinary car.'

They were streaking along a comparatively straight stretch of road when, to her horror, Jo saw that a main highway was cutting across it at right angles.