'No,' the Doctor replied. 'No. That's the wrong question too.'

'So what's the right question?'

'Ah. . . that I don't know. I was hoping that together the two of us the three of us, sorry, Rachel could come up with it.'

Marnal's patience had run out. 'I've answered the only question that matters.'

122.

'ARMED POLICE! WE HAVE YOU SURROUNDED!'

The Doctor winced. It was to the point, he supposed, but couldn't the officer have thought of something more elegant?

'You called the police?' Marnal shouted. 'This is your idea of a truce?'

'What did you say to them?' Rachel asked.

'I just said who I was,' the Doctor said. 'And that you had a gun and a hostage, but I was fine, I'd sort it out, so there was no need for them to come round.'

Marnal was walking over to retrieve his gun.

'Look, Marnal, I meant what I said before.'

Marnal tucked the gun away. 'Only you could break a promise before you even made it,' he said.

A squad car had been three streets away when the 999 call had been relayed to them. A couple of young constables had turned their car around and come straight to the house. They'd been warned that there was a hostage situation, and that the kidnapper was armed, so while they waited for back-up they confined their activities to a.s.sessing the situation and getting the neighbours to stay indoors and away from the windows. Another two cars arrived within minutes, along with an ambulance. One of the new cars had brought an inspector, who took control of the scene and had the officers establishing an inner and outer cordon. By now, a van with officers in body armour had arrived, along with a couple more cars. The vehicles were parked to block the road off and provide a corral for the officers staking out the building.

The police knew very little. A man had phoned 999, given them this address and said that someone was being held hostage, probably in the detached garage. The hostage-taker was a man in his thirties wearing a distinctive blue blazer, and he had a pistol, a taser and possibly other weapons. There were only three people on the premises. Then the caller had hung up. The phone call had come from the landline of the house itself. The two officers who'd been first on the scene reported what the next-door neighbours had told them: there was one resident of the house, an elderly man who the neighbours thought had been at death's door. Most days, his nurse came round for a few hours.

Hostage situations took one form pretty much the whole world over the authorities waited, did nothing to provoke, established a line of communication and tried to find out what the hostage-takers wanted. It was a game, of course. The police weren't going to give in to their demands, and only the most deranged hostage-taker thought otherwise. The moment the siege started there were only two outcomes: the hostage-takers either eventually gave themselves up or they started shooting. If the latter happened, this was 123 the point where the authorities had nothing to lose and went in hard. Just out of sight, an armed response unit was already drawing up plans and checking automatic rifles. If it came, the a.s.sault would be over in seconds.

The Doctor was telling Marnal all this while reading one of the books he'd brought from the cellar.

'I've often thought about writing a novel,' the Doctor confessed. 'Never seem to find the time. I suppose that when I retire, I'll give it a go.'

'They say everyone has a novel in them,' Rachel said. 'I don't think I do, though.'

'Perhaps that will change after tonight,' the Doctor said.

Marnal was pacing around the garage. He had the gun back in his hand, but knew he couldn't fire it without provoking a police response.

'You could always put the telly on,' the Doctor suggested, indicating the gla.s.s bottle.

Marnal snarled at him, then to the Doctor's surprise followed this suggestion and turned on the device. After it had warmed up for a little while he tuned it into their surroundings. Outside the garage there were dozens of police, almost all of them kitted out with body armour and guns. Marnal panned around, looking for a way out that he'd missed, but it was a small garage with only one entrance. It wasn't that difficult for the police to cover every angle. There were armed men kneeling behind every garden wall and waiting round every corner.

'Why don't we just leave in the TARDIS?' Rachel asked Marnal.

'The recalibration won't be complete for hours, possibly not until this time tomorrow.'

'Recalibration?' the Doctor spluttered, finally putting the novel down. 'What are you doing to her?'

'Fixing her, Doctor. You've neglected even basic maintenance work.'

'If it isn't broken, you don't fix it.'

'Less than 10 per cent of the ship's systems are working as they should.

Everything else is either malfunctioning, barely working or entirely missing.'

'Piffle. It may be missing a cupholder here and an optional extra there, but the TARDIS is fine. Name one thing that's important that's not working.'

'The absence detectors, all of the aesthetics gauges, the ahistorical contex-tualiser, the ambiguous resolver, the animal-language translation circuits, the aprioritron, the art device, the a.s.similation contrastor, the axiomator, the '

The Doctor waved his hand. 'All I really need is something that gets me from A to B.'

'WE KNOW YOU'RE IN THERE. WE WANT TO TALK TO YOU.'

The gla.s.s bottle showed a middle-aged inspector holding up a loudhailer.

124.

'We're going to be here for a little while,' the Doctor said. 'Why don't we try to work out what happened on the Edifice after the events we saw? Or what's behind the back wall. The answer's on the tip of my tongue.'

'Perhaps you've got Gallifrey behind there,' Marnal sneered.

'Perhaps I have,' the Doctor admitted. 'If I did, it would have a bearing on my case, yes?'

Rachel was looking glumly at the bottle. 'I don't think I want to know my future right now.'

'You can tell the future with that thing?' the Doctor asked.

'Come, Doctor, surely you recognise a '

'Oh, give it a rest, will you? I thought it just showed repeats.'

The Doctor moved over to the bottle. 'We could use this to see how the siege ends,' he suggested, twiddling away at the k.n.o.bs and dials.

A quiet beeping noise started up from one of the components.

'Oh, I see how you tune this in now,' the Doctor said. 'This is really rather clever.'

'Can anyone else hear that sound?' Rachel asked.

'Nothing to worry about, I'm sure,' the Doctor said dismissively.

'It's coming from the fusion reactor,' Marnal said.

'The what?' The Doctor twisted round to look at the silver cylinder. 'This is a nuclear bomb?'

'A cold-fusion generator.'

The Doctor touched the side, then withdrew his hand. 'It's hot.'

'You've broken it,' Marnal said, incredulous.

'Broken it?'

'The regulators have failed. The energy is increasing exponentially.' Marnal was already heading for the TARDIS.

'There's going to be an atomic explosion?' Rachel screamed.

'You could come with me,' Marnal offered, almost as an afterthought. 'Even immobilised the TARDIS is indestructible. We'll be able to ride out the blast.'

He unlocked the TARDIS door, and opened it. 'I'm sure the Doctor can defuse the reactor. If not, then. . . well, I doubt he'll feel anything.'

'Your books will be destroyed,' the Doctor countered.

Marnal's foot hovered over the threshold. 'I '

'Don't worry about the books. One of you do something before a million people die,' Rachel shouted.

'No one dies,' the Doctor replied.

He unclipped the fusion reactor and tossed it through the open TARDIS door.

'What are you doing?' Marnal cried.

'Close the door!' the Doctor yelled.

125.

Marnal was paralysed, but Rachel grabbed the door handle and yanked it shut.

The Doctor hurried over and patted the TARDIS.

'Brace yourself, old thing.'

They didn't hear the explosion and the outside of the TARDIS didn't so much as shake.

Inside, the heart of a star appeared just inside the door, a light so bright it obliterated everything. The books and the bookshelves and the antique furniture and the candles and the kitchen and the food machine and the fault locator and the lamps and the hat stand and all its hats, scarves, coats and the shaving mirror and the carpets and the gramophone player and the chairs and the wine rack and the chess sets and the ormulu clock and the full-length mirror and the table and the tea set on the table and the b.u.t.terflies and the tool kit and the cuddly toys didn't have time to catch alight, they were simply gone.

The column in the centre of the room was made of sterner stuff the forces at the heart of a sun were nothing compared with its usual fare but the console blistered and caught fire. The walls were tough and swirled the energy around and then out of the room, through the one open door leading off into the depths of the ship.

An irresistible wall of flame surged down the corridor, seeking any opening.

Flames rolled around Fitz's room melting every record, every souvenir, every trace that he or Trix had ever been in there.

The fire crashed through the TARDIS laboratory, smashing every piece of equipment and the benches they were on.

A wardrobe the size of an aircraft hangar became an inferno, rack after rack of clothes catching alight, the racks themselves twisting and melting.

The swimming pool boiled dry, the cloisters were scoured clean of ivy.

The firestorm raged on.

Marnal was shaking.

'What have you done?'

'He saved the entire population of London,' Rachel answered.

'WE HEARD SCREAMING. YOU HAVE TO SHOW US THAT YOUR HOSTAGE IS SAFE.'

'There are billions more human beings that's the last surviving TARDIS in the entire universe.'

'This is just a thing, not a person.'

The Doctor was barely aware of them. He was counting. When he'd waited precisely long enough, he turned the key to open the door.

126.

'Wait!' Rachel shouted, but the Doctor didn't. He flung open the door and s.n.a.t.c.hed the key out of the lock, then stepped aside for a second to avoid the blast of burning air. A backdraught of new oxygen fanned the flames, which quickly subsided.

The Doctor pushed his way through the door, eyes closed. The floor was crunching beneath his feet. He knew his TARDIS, and the distance to the console, but the smell of ash and the sheer heat of the air were terrifying. He was ready for the step up on to the dais in the centre of the control room, and groped his way around the console. He s.n.a.t.c.hed his hand away from a red-hot piece of bra.s.s, and briefly lost his bearings. So many of the b.u.t.tons and instruments had been wrecked. He risked opening his eyes, and forced them to stay open in air so dry it stung, as he found the controls he was looking for.

He slammed the palm of his hand down on a b.u.t.ton.

It began raining in the TARDIS.

Primitive sprinkler technology, but as effective as any more exotic method of putting out a fire. The water doused the last of the flames and, most importantly, it cooled the room. The Doctor looked around to find the it gutted.

The whole room was stripped empty, the walls smudged with great streaks of soot. The bare floor was a maze of fine cracks. The console was the only thing that was still there. Water was running off it, on to the floor and down the plugholes that had just opened up.

The Doctor bolted the door then wiped some of the damp ash from the panels, trying to get a sense of the damage from the ruined displays. The TARDIS was able to repair its own structure, given some time, but wouldn't be able to replace the contents he and his companions had ama.s.sed during their travels.

He slipped the book bag off, and tucked it under the console to keep it dry.

Checking what monitors he could, the Doctor was almost absurdly grateful to discover that two of the TARDIS's three great libraries had survived unscathed. The walls of the TARDIS were strong, and the old girl had a strong defensive instinct. Emergency barriers had come down, keeping the blast away from the engines and other critical areas, channelling the energy towards. . .

The Doctor started running.

He followed the route the firestorm would have taken, licks of soot on the wall pointing the way like road signs. He left the console room and entered the main corridor to the depths of the ship. The walls were still warm, but there was little here for the fire to take. Where the hatches hadn't been bat-tened down, it would be a different story. He pa.s.sed an open door and had enough time, even running past, to see that Fitz's room was a ma.s.s of charred wood and twisted remains.

127.

This wasn't his most pressing concern.

The Doctor instinctively knew some of the principles that controlled the TARDIS, and he'd picked up more on his travels. At the heart of the TARDIS was the immense source of the energy that travelling through time and s.p.a.ce required. When the TARDIS had been built, it had drawn its power from a link with his home planet: Gallifrey. The Doctor himself had also had some connection to the place. He'd suffered physical side effects for a long time, until that business in Henrietta Street in fact, because the link with home had been broken. The TARDIS, though, had survived. The only inference was that it had, at some point long before the destruction of Gallifrey, been fitted with an independent source of energy.