'I do! I do! It's just I feel it would be more appropriate to take things slowly. You know, correct procedures...

protocol...' She feels her voice slip away. They're not going to do it, she realises, grimly. 'All right. How about if I beg?'

She looks at Prahna's stern brown face. 'I guess that wouldn't work either,' she mutters.

'You know our orders,' says Prahna. His expression has gone cold; the soldier coming through.

'Aren't you at least curious?' asks Erik.

You want the simple answer, Pelham thinks. She realises she is locked up with two madmen. All of a sudden, the bangle on her wrist itches like h.e.l.l. Not yet, she thinks.

Conceivably, this might not be the actual worst. Not worst enough to face... well, not yet anyway.

'OK, OK. Let's just get it over with. And in answer to your question, Erik, no I am not in the least bit curious. I'm incredibly scared. That's what I am.' Pelham feels herself starting to sob.

'We must go on,' says Erik.

'We have to go on,' says Prahna.

The bathyscape swings once more. Perhaps everything is going to be OK.

'Er...' Prahna seems sheepish. He leans back and stares at his controls.

What is she thinking? Of course everything isn't going to be OK. Pelham grabs Prahna's shoulder, digging her long, red nails into it. 'What is it? What's going on?'

Prahna spreads his hands out, indicating the dials and levers as if she's never seen them before. 'They're moving on their own,' he says. 'I'm not in control any more.'

'A chronometric pulse?' asks Romana, clearly not believing a word.

'A chronometric pulse,' the Doctor rea.s.sures her. 'A wave of dimensional energy.'

The TARDIS has stilled, for the moment. Mind you, the explosion that blew the tracer out of its nest on the console was a little worrying. Luckily, the Doctor was in just the right position to perform a dynamic double-handed catch before banging his head on the floor.

Blackened, almost chastened, the panicked travellers have hurriedly disa.s.sembled the tracer's components and are probing for damage. The Doctor squints, jeweller's gla.s.s in one eye, and hopes he can put this infernally complicated device back together again.

He waves away Romana's attempt to bandage his head.

'There's no such thing as a chronometric pulse,' she says.

'Then what you experienced was impossible. Still, not to worry. We'll just let it ride and when the universe tears itself apart you'll know that that's impossible too.'

'That's not funny.'

'I'm not joking.' The Doctor looks up, the jeweller's gla.s.s still lodged in his eye. 'What do you find so impossible? That this could have happened? Impossible is just another word for "I don't understand".'

Romana backs away, unsure of herself. She's only been with the Doctor for a short time but already she knows that events aren't always controllable, or foreseeable. She decides to check the tracer's slot on the console for damage.

'A release of trans-dimensional energy,' she mutters to herself. 'The result of a rift between the lower and higher dimensions of matter. A rift in the kinetic dance. In theory.'

'Theory my eye,' says the Doctor, the jeweller's gla.s.s dropping from his. 'It's the only possible explanation. What else could have done this to the tracer? Or the TARDIS?

There, I think it's done.'

He rises, ready to plunge the tracer back into its slot.

Romana looks on in horror. 'Aren't you going to test it? How do you know you've mended it correctly?'

The Doctor smiles. 'Test it? It's perfect!'

And with that he slams the tracer into place. The TARDIS lurches, tumbling once more.

'Teething troubles,' he grins, once he has untangled himself from the coat stand. Romana can only shake her head.

Almost not wanting to, they look at the console. The tracer is back in place, lights pulsing merrily.

'Seems to be functioning,' says Romana.

'Of course it is. And if I know my dimensional engineering, the location of the second segment should appear any second. Minute. Within the hour. Today.'

They wait. No readings, coordinates or information of any kind appear on the console screen.

'Doctor...' Romana warns.

'Well, it has got the entirety of s.p.a.ce and time to search.

You can't expect miracles. That's the trouble with you Academy types these days, no patience.'

Mind you, he does slam his fist down on the console and yell, 'Come on you stupid overgrown pencil!' at the innocent device, confirming Romana's view that the Doctor suffers from psychological cognitive dissonance and a fixated egocentric maturity deficiency. As Garron might have said: he's a big kid.

'Maa-ssterrr...' comes a sorry-sounding voice from the shadows.

The Doctor spins. 'K-9,' he utters, shocked. He leaps down to his forgotten companion.

'Maa-ssterr...' it says again, voice slurred, unmistakably mournful.

The Doctor hurriedly hauls the dog into the light.

'Doctor,' says Romana, frightened. 'His eyes. What's wrong with his eyes?'

The Doctor, on his knees, shuffles away. He is breathless, taken aback by the dog's plight. 'Oh, K-9.What's the matter?'

The dog's ears waggle feebly; mangled electronics grind deep inside its casing. 'a.n.a.lysing tracer malfunction... Great forces... Chasms...' it says, 'breach fabling...'

'What's he saying?' asks Romana. 'a.n.a.lysing the tracer?'

The Doctor strokes K-9's metal aerial, an aerial that is telescoping up and down. 'Too much initiative, too impulsive.

He must have tried to run his own diagnostic program when the tracer went dead. I think he's picked up some kind of trans-dimensional feedback loop that's scrambled his circuits. Either that or he's drunk.'

There is something disturbing, something cold and remote about the black husks that seem to have grown over K-9's ocular sensors. Shining discs, like the eyes of an insect.

Almost blurred, not of this reality. Romana is reminded of the segment of the Key, the way its alienness is fascinating, hypnotic.

'Don't look at him!' shrieks the Doctor suddenly and hurls himself at her. 'Look away!'

'Poor steam...' says K-9, backing away from the light. 'Meet here...'

The grinding inside ceases and its head droops.

The Doctor holds Romana tight, too tight, but he is looking at the shadows where the dog lurks. 'Doctor,' she says, smoothing back her hair. She puts on her best haughty look.

Anything to cover the fear that she suspects she feels. 'I'm fine.'

'The higher dimensions,' whispers the Doctor. 'How could they... affect a machine?'

'Almost nothing is known of the higher dimensions,' says Romana. 'Except that they exist... co-exist with this universe.

A part of reality...'

'A part!' The Doctor finally releases her. 'They are reality!

Total reality! More reality than even pompous Time Lords can perceive. Somehow, it's made itself apparent here.'

'How?'

'The chronometric wave. A release of trans-dimensional energy. We're still on the sh.o.r.e. The real events are taking place out there, deep in the ocean.'

'Doctor, you're talking in riddles.'

'Am I? Sometimes that's the only way to make oneself clear.'

'Aren't you forgetting something?' Romana asks.

'Me? Forget something? Never.'

She points to the segment, miraculously still sitting placidly on the white table. 'Our task?'

The Doctor seems trapped. He stares alternately at the segment, then K-9, then back to the segment again. 'How could I... ? But wait. If something is causing the higher dimensions to become apparent. Perhaps the Black Guar'

'The what?'

'Never mind. It's just that it might be a trick. To divert us.

But we can't take that chance, can we? The Key to Time must be paramount.'

A bleeping comes from the console. Romana glances over.

'Perhaps the decision has been taken for us. These coordinates. Oscillating. All over the place.'

The Doctor stares at the hesitant numbers. 'It could be that the forces are upsetting the tracer's circuitry.'

'Or you rebuilt it incorrectly.'

'Impossible. If that's not working, how can we be sure where the segments are? It could send us anywhere.'

At last, the turning numbers settle. A coordinate, a place.

Romana knows she doesn't need to look it up in the star charts. He knows. He always knows.

'Ashkellia,' says the Doctor. 'Interesting.'

'Really? In what way?'

He sighs, as if talking to an idiot. 'Because, as everybody knows, it's reputed to be one of the resting places of Valdemar. This is all starting to add up.'

'Not to me it isn't.'

'Well, of course not. You probably don't even know who Valdemar is.'

'But you're going to tell me.'

'On the way. We have to materialise whether it's the second segment or not. If for nothing else, for K-9's sake.'

Romana glances back at the machine. It sits, motionless, as if waiting for a command. She feels in need of some distraction therapy, some task to marshall her energies, as she was taught during the training she received on Gallifrey.

One action always focuses her mind. 'I'd better pick some suitable clothes,' she says sternly. 'What sort of planet is Ashkellia? Not cold again, I hope.'

The Doctor seems distracted, barely listening. His eyes don't leave the coordinates. 'Cold? Oh no. Quite the opposite.'

Pelham, when she's not praying or trembling, watches through the portholes in the floor as the black shape below grows bigger. Luckily, the sensors are still working and Erik is very helpfully deconstructing just wherever it is that whatever it is that has them, is taking the bathyscape.

'Some kind of artificial stone construction. Too dense for any kind of clear reading on these sensors. Just tough.'

'It would have to be,' says Pelham, almost to herself, 'to have survived here without melting for a million years.'

Prahna, now without anything to do, can only get in the way. 'A million years?'

'That's my estimation as to when Valdemar was entombed by the Old Ones. They're called "Old Ones" for a reason, you see,' she says sweetly.

'You know, I never thought it was real, all this Valdemar stuff. It's just that Neville...'

'I'm glad I'm down here with you. So I can share in your life story.'

'Hush!' says Erik (' Hush Hush'? Only Erik would actually say ' Hush Hush'.) 'I think it's opening up. The top... it's opening up.'

One good thing about whatever is now driving the bathyscape is that the ride is a lot smoother. Pelham can actually see see. Whether or not she wants to see, is another matter.

The bathyscape drops into darkness, through the top of the construction that appears to have found them. Prahna activates the docking lights. They don't help much; the walls of the well are obsidian, black and smooth. It's hot still.