The seconds that Martha and the Doctor's eyes were locked, seemed like an eternity. Then the Doctor's snarl broke the spell, she let out a cry of alarm and fell back as the Doctor moved.

He was snarling something, but she realised it wasn't directed at her. He moved with that Time Lord speed, not towards her but past her.

It still hurt when he pushed her aside and into the wall. Why wasn't Jack reacting?

Her answer came seconds later when the sound of machinery filled the air. It was coming from the walls….then it came to her, she'd forgotten; retractable chains.

Everything happened quickly as the chains did their job. The Doctor was reeled back, hard and painfully.

"Martha, out now," Jack said,

She got up and said, "Be careful," before walking out of the cell, then standing and watching.

Jack leant against the clear front, watching as the Doctor raged. Eventually he said.

"The more you struggle, the tighter they'll get. So, unless you want to lose several limbs, I quit moving."

The Doctor stopped, but he knew it wasn't because of his words.

When the Doctor spoke, there was no trace of anger; he sounded clam and reasonable, which Jack didn't fall for at all.

"Seems you have me at a disadvantage…again. I really must be slipping. Still, it makes life interesting."

Jack knew the casual tone in the Doctor's voice was the time to keep your distance; the Doctor was at his most dangerous when he seemed calm. But he needed answers, answers to what Ash had said.

"So, I had an interesting conversation with Ash."

He watched the Doctor closely, looking for a reaction.

"That's nice, did you exchange recipes?"

"Afraid not, although he did seem to think he wouldn't be staying long. Why is that?"

"Not a clue, I'm not a mind-reader."

Jack let out a snort, "Well, that's bullshit. If Ash is saying that, then I damn well know you know something."

The Doctor's eyes narrowed and then he gestured at the chains.

"Even if I was inclined to talk, these aren't exactly conducive to conversation."

"Not coming off."

"Oh, learnt your lesson then. But, he was right, he…well we won't be here long, and there's nowhere on this planet you can hide my sons, that I won't find."

Jack didn't show his concern, but the Doctor sounded way too confident.

"Got someone on the outside, have you?"

He didn't like the sly look the Doctor gave him.

"Well, that's for me to know and for you….I won't spoil the surprise."

"What, that ego of yours not going to tell me?"

"Err…no, think I'll leave it as surprise. I know how much you hate surprises."

Then the Doctor said it again.

"Tick-tock, the clock is ticking."

"What does that mean, or are you just talking crazy talk?"

Again there was that sly smile.

"Tick-tock, where will the hand stop? Will it be tick or will it be tock? You better watch the clock."

Now the Doctor was spouting rhymes at him. There was no doubt the Doctor was mentally unstable, but he still had the feeling that underneath the surface of insanity, something dark and very dangerous was lurking.

The Doctor was speaking again, and once again he seemed calm and reasonable.

"You know, if you remove these, I might be a tad more co-operative. It's not like I'm going to escape. It's actually safer for me in here…for now."

Again, there it was, the hint that something was on the horizon. But how could he trust anything the Doctor said when it was tinged with insanity.

Tick-tock," the Doctor said again, this time accompanied by a non-to sane laugh.

Jack sighed, he wasn't going to get anything out of the Doctor either. All he got was the feeling that something nasty was coming, and he didn't know what.

The Doctor smiled as he watched Harkness leave the cell and start talking with Martha Jones. He'd enjoyed playing with Harkness. He was never going to get whatever it was he wanted out of him.

He could play this game forever…well, until it was time; let Harkness try and work out the riddle.

That said, he hoped the Master would arrive in time to witness his big reveal. He knew he would like what he had created. The devastation would be well… devastating. He flexed his arms, felt the chains tighten and relaxed; he would have to wait.

"I don't like it," Jack said. "He's up to something, I know it."

"He could just be playing with you," Martha said. "He isn't exactly in a position to make any threats."

Jack shook his head, "I don't know. If was just him, I say yes, but its Ash saying it as well. If I know the Doctor at all, he always has something up his sleeve."

"You do know that eventually word will get out that he's back in custody. You'll have Washington on your back soon, and I don't think UNIT will be able to put them off."

"Don't worry, I'll handle them. As long as the boys are out of their reach, it'll be fine."

"They're safe," Martha said. "But Jack, we can't put off discussing his future. Flat Holme doesn't exist anymore, and I doubt any high security facility could hold him. I don't even know if this place will hold him, it hasn't before."

Jack sighed, "I know, but I can't and don't want to put him in stasis. I know you think he's spouting rubbish, but I just get the feeling that something huge and not good is going to happen."

Ianto motioned to them as they climbed the last step.

"Not sure what he's doing…"

They looked at the monitor, the Doctor had stretched his arms as far as the chains would allow, and was tapping his wrist with one finger and was saying something that looked very much like.

"Tick-tick."

As volcanoes go, this one had never been that active, so it had never really been monitored or studied, apart from your basic seismic monitor. So the increase in tremors was recorded but not sent to the small monitoring station that sat near the much larger and much more active volcano.

So it's small camera wasn't activated, so there was no film as the earth around began to move and separate, nor did it have time to send out the alarm as something white hot grasped it with a clawed hand and crushed it from existence.