The Doctor was illuminated in golden light, regenerating. Suddenly, he put his hands together and pointed them at the glass jar with his hand in it. The regeneration energy beamed out from his hands, pouring into the jar and the hand began to glow. The water in the jar began to bubble. The regeneration energy was absorbed by the hand and the light fades. Scarlett, Captain Jack, Donna and Rose all looked up as the light disappeared. The Doctor stumbled back, out of breath, but still the same person. He breathed heavily, as each of his companion's stared at him in shock. Rose and Donna were still teary-eyed.

"Now then," the Doctor states cheerily, "where were we?" He heads towards the console. Donna stares at him, while Rose and Captain Jack continue to stare at the spot where he has just been standing, stunned.

Scarlett stared at the Doctor and swallowed hard. Doctor? She pushed weakly towards him as he moved towards the hand in the jar and knelt down before it. Are you okay?

I'm brilliant! he cheerily replied, mentally. Then she felt concern wash over him. How are you? Oh, that was painful wasn't it. Oh, I wish I could come to you.

I'm feeling a bit tired. When you began to regenerate it was like – She leaned her full weight against one of the coral columns of the TARDIS – it was like a part of my brain was ripped out—but you're back?

She felt him push an affirmation her way then heard him in her mind one last time. This is going to take a lot of focus, this act, I won't be able to communicate much more.

The Doctor smiled wide at his golden hand in the jar, still glowing with regeneration energy. "There now," he spoke affectionately and then blew away all of the regeneration energy, leaving the hand simply bubbling in the jar. He grinned, then sat up on his knees, his arm leaned on the console, as he looked at the rest of the companions.

"You see!" the Doctor began his explanation enthusiastically. "Used the regeneration energy to heal myself, but soon as that was done I didn't need to change, I didn't want to, why would I? Look at me." He smugly adjusted his tie.

Donna had noticed Scarlett leaning against the column and stepped over to her. She nudged at Scarlett's mind to communicate with her. Their first time since everything had happened outside the TARDIS. Scarlett? Are you okay?

The Doctor continued, noticing out the corner of his eye that Donna was attending to Scarlett. It pleased him to see his best friend showing Scarlett such concern. Especially because he couldn't. He continued his explanation, "So, to stop the energy going all the way I siphoned off the rest into a handy bio-matching receptacle. Namely, my hand. That hand there. My handy spare hand."

Scarlett gave a weak smile to Donna. Oh, I'll be fine. Just need a bit of time. When the Doctor's regeneration began, it was as if a part of my mind was ripped away suddenly, before reappearing moments later. A bit jarring, that's for sure.

He stood up then and addressed Rose, "Remember, Christmas Day, Sycorax? Lost my hand in a sword fight. That's my hand." He paused a moment, then smiled at her. "What do you think?"

Donna frowned at Scarlett. Why isn't he checking on you? Surely, he knows what's going on?

Scarlett signed mentally. We—talked—he can't, it would make Rose too suspicious.

Rose watched him, her expression somewhat sad. She stepped towards him cautiously. "And you're still you?"

"I'm still me," the Doctor responded, and Rose smiled and hugged him tightly. Over Rose's shoulder, the Doctor glanced a moment at Scarlett then closed his eyes and continued to embrace Rose.

Captain Jack smiled genuinely, but his top lip twitched as he noticed the Doctor's line of sight change for a moment. Donna and Scarlett, having seen the exchange, give their best attempt at smiles, playing along. Donna turned to Jack. "You can hug me if you want."

She grinned. Jack looked between Donna, Scarlett, then at the Doctor and Rose, and laughed nervously.

"No, really, you can hug me," Donna repeated herself, and Jack's expression grew serious.

He pulled her aside, towards Scarlett, doing his best not to distract the Doctor and Rose. He began whispering, "Look, I don't know what's going on here, but I can tell something isn't right." He looked to Scarlett and continued, "I know you don't know me from Adam, ma'am, but I'm hoping eventually you'll trust me enough to explain. In the meantime, can we cut the theatrics a bit?"

Just then, the console started beeping. The Doctor released Rose and ran to the console to check on what was going on. Scarlett moved to stand next to Jack and looked on. Rose pretended to be working at the console, obviously wanting the others to think she knew what she was doing, although Scarlett knew that she never learned how to pilot or work the TARDIS properly.

Suddenly the TARDIS seemed to shut down. Briefly, Scarlett wondered if Rose had accidently hit the "off" switch. Was there an off switch? But she surmised by the Doctor's behavior it must have been more complicated.

"They've got us. Power's gone!" he shouted as he ran around the console, dodging each of them as he checked controls. "We're stuck in some kind of chronon loop."

Suddenly they were jerked around as they were pulled up off Earth and towards the Dalek ship. Jack, having already learned a lot while addressing the threat at Torchwood, explained, "There's a massive Dalek ship at the center of the planets. They're calling it the Crucible. Guess that's our destination."

Scarlett stood up straight, having regained enough strength. Donna was satisfied by this and turned her attention to the Doctor. "You said these planets were like an engine. But what for?"

The Doctor answered by turning to Rose and questioning her, "Rose! You've been in a parallel world, that world's running ahead of this universe, you've seen the future, what was it?"

Rose stated matter-of-factly, "It's the darkness."

Donna acknowledged her response. "The stars were going out."

Rose nodded, then continued, "One by one. We looked up at the sky and they were just dying. Basically, we've been building this, um—this travel machine, this—uh, dimension cannon. So—well, so I—well I could—"

Scarlett felt as if she might be sick, and not because of her mental recovery. This is what the Doctor had feared. Her nausea got worse as he played his part with precision.

"What?" the Doctor asked her innocently.

"So I could come back." She grinned and the Doctor returned it.

She gave her best flirtatious smile. "Shut up." She paused a moment as they smiled at each other, then continued, "Anyway, suddenly it started to work. And the dimensions started to collapse, not just in our world, not just in yours but the whole of reality, even the Void was dead. Something is destroying everything."

Donna wanted to respond to her, Yeah, maybe it's you?

At the same time, Scarlett was doing her best to stay calm.

Donna glanced at Scarlett in concern, and Rose noticed, turning to her as well. "So, who are you?"

Scarlett stood up straighter, cautious of how to respond. "I'm Scarlett—just a friend of the Doctor's, here to help." She gave her best smile and reached out to shake Rose's hand.

Rose has moved so the Doctor was behind her. He let a faint look of concern wash across his face that Donna glanced and noticed, then she saw him go back to his act. Donna decided she was going to need to intervene to keep the questioning from going further, she stepped closer to Rose. "In that parallel world, you said something about me."

Rose shook Scarlett's hand tenuously, then turned to Donna as she spoke. "The dimension cannon could measure timelines. It's weird, Donna, but they all seem to converge on you."

"But why me?" Donna continued to question why she was so important that these so-called timelines would be finding her so important. The Doctor stared at her as she continued, "What have I ever done? I'm a temp from Chiswick."

The monitor bleeped suddenly, interrupting their conversation before the Doctor could once again correct Donna on her negative self-view. He turned to the monitor and found the Crucible flashing red on the screen, surrounded by the twenty-seven planets.

"The Dalek Crucible. All aboard."

The TARDIS made its final journey towards the Dalek ship, getting pulled in through a chute, and into the chamber with the Supreme Dalek.

"Doctor, you will step forth or die," they heard the voice over the TARDIS comms.

The Doctor looked around at each of them while speaking, "We'll have to go out. 'Cause if we don't they'll get in."

Rose spoke up, "You told me nothing could get through those doors."

Jack added, "You've got extrapolator shielding."

Having walked part of the way towards the door, the Doctor turned around to face them. "Last time we fought the Daleks they were scavengers. And hybrids, and mad. But this is a fully-fledged Dalek empire. At the height of its power. Experts at fighting TARDISes, they can do anything. Right now, that wooden door is just wood."

Scarlett was the only one to notice the look on Donna's face. She had grown distant, like she was hearing another voice in her head. The Doctor, Jack, and Rose were busy discussing other escape options. Rose's dimension jump, Jack's teleport—with no other options, the Doctor spoke to all of them again, "Right then. All of us together."

Donna hadn't heard a word they were saying for a few minutes. It was that heartbeat sound again, just like she heard at the Shadow Proclamation. But stronger. Louder. Her eyes grew teary.

Finally, the Doctor noticed something was wrong. "Donna?" She continued to be non-responsive so he walked over. "Donna!"

Finally, she turned and looked at him, surprised. "Yeah."

"I'm sorry." He squeezed her arm. "There's nothing else we can do."

She nodded. "I know."

The Doctor nodded back and turned back towards the doors. Over the speaker came the voice of the Supreme Dalek again, "Surrender, Doctor, and face your Dalek masters."

Another Dalek voice was heard, "Crucible on maximum alert."

Rose smiled and laughed nervously. "Daleks."

"Woah god," Jack responded and laughed too. They both smiled brightly at The Doctor when he turned back around.

"It's been good though, hasn't it?" The Doctor looked at each companion. Donna smiled fondly at him. "All of us. All of it. Everything we did." He turned to Donna and Scarlett, who was close behind her, though they were both still up by the console. "You were both brilliant." She smiled then he turned to Jack. "And you were brilliant." Jack grinned and the Doctor turned to Rose. "And you were brilliant." Rose smiled, then the Doctor's eyes went a bit wide as he stared towards the door. "Blimey—"

As he turned, his expression became grave. He walked out, with Rose following him, then Captain Jack. Donna took a deep breath then started to follow them. She noticed Scarlett moving a bit slower and turned to take her arm and walk with her.

The Doctor stepped out, hearing the chanting of the Supreme Dalek and all the others. He was shocked as he looks around seeing hundreds of Daleks. The Doctor began to walk away, with Rose and Captain Jack following.

Inside, Donna stopped momentarily at the door, the two women straightening themselves to begin to walk out in single file, but Donna turned as she started to hear the heartbeat again and looked towards the console.

"Donna!" the Doctor shouted back towards the TARDIS "You're no safer in there!"

Donna frowned and turned back to the door. It slammed shut. The Doctor ran to the door and inside, Donna and Scarlett both hit at it, trying and failing to get out.

"Doctor! What have you done?" Donna shouted.

"Doctor!" Scarlett shouted.

"It wasn't me." The Doctor tried to get the door to open. "I didn't do anything!"

"Oi!" Donna shouted and rattled at the door. "Oi, I'm not staying behind!"

The Doctor turned to the Supreme Dalek. "What did you do?'

The head Dalek responded in anger, "This is not of Dalek origin."

Donna continued to slam her hands against the door. Scarlett slowly began to walk backwards back up the ramp, her face pale as she sensed that something bad was about to happen.

The Doctor shouted at the Daleks, "Stop it! They're my friends! Now open the door and let them out."

The Dalek didn't believe the Doctor. "This is Time Lord treachery."

The Doctor pleaded with him, "It wasn't me, the door just closed on its own!"

"Nevertheless," the Dalek continued heartlessly, "the TARDIS is a weapon and it will be destroyed!"

The floor beneath the TARDIS disappeared and it dropped down a chute. Inside the TARDIS, Donna and Scarlett get knocked off their feet as things crashed and broke around them. The Doctor ran to the gap in the floor where the TARDIS had been and looked down, watching it fall.

"What are you doing?!" He shouted, "Bring it back!"

The TARDIS continued to fall down the chute, Donna clung desperately to the railings inside. Scarlett fell to the floor and clung to the edge of the console.

Donna yelled out into the air, "Doctor!"

The TARDIS fell into a massive ball of liquid fire at the core of the Crucible. Inside, the lights exploded one by one, and fire raged through the grating. There were crashes going off everywhere. Donna screamed, then got to her feet and ran over to the console by Scarlett. Donna fell to her knees. Observing the destruction around her, Scarlett knew their time was short. She closed her eyes, a tear falling down her cheek, and quickly slammed down a mental wall between her and the Doctor. He's standing in the middle of a swarm of Daleks, she considered. If he endures my death in his mind the way I felt his regeneration, he'll lose focus on what he must do to survive.

An explosion at the console distracted her. She pulled herself over to where it was, and as she started to stand a fire exploded at her feet, burning her leg. She fell to the ground, screaming in pain.

Donna let out a choking sob. Suddenly, she started hearing the heartbeat once more. She turned to the severed hand in the jar, which was glowing and bubbling. In a daze, she slowly reached out for it.

Scarlett looked over and saw Donna's hand nearing the jar. "No, Donna, don't!"

Donna didn't hear her, and she continued to reach and touch the jar. Golden regeneration energy began to pour out of the hand, drifting around Donna. Suddenly, the jar exploded in a flash of gold.

Scarlett pulled herself up off the grating and tumbled over to Donna. She wasn't sure what was happening but as images flashed into her mind, she quickly stretched out and touched Donna's head with one hand, and with the other hand she touched the fingertips of the severed hand that now laid on the grating. The energy wrapped around her as well, seeming to ebb and flow between the three of them before fading out. Donna and Scarlett collapsed to the floor.

A moment later, Donna sat up. She saw Scarlett laying beside her in a heap and then watched as the Doctor's hand glowed brightly, and an arm slowly began to fill into the empty space, growing out it. The fingers twitched. The body of a man continued to grow from, and form out of, the golden regeneration energy, while Donna watched in amazement. The golden figure sat up suddenly, and the golden light drifted away to reveal a duplicate of Doctor's sitting there, staring straight ahead, with no clothes on.

Donna pushed herself away in shock. "It's you!"

The Duplicate Doctor exclaimed smugly, "Oh yes!"

Suddenly they were both taken by surprise as Scarlett sat straight up, eyes wide. She turned quickly to each of them then reached her hands out and touched their temples. Their eyes slammed shut as they felt her accessing their minds in a rush of information. The swirling of information flying around in their heads was too fast for them to tell what she was doing. Then, just as suddenly as it started, it stopped. They opened their eyes to see Scarlett's arms fall to her sides and she collapsed again, passing out.

They both looked quickly between themselves and Scarlett. Then, Donna's eyes flicked downwards before she looked away. "You're naked!"

He smirks again. "Oh yes."

Donna glanced down at Scarlett. "What did she do to us?"

"Not quite sure." The Duplicate Doctor looked into his own mind, trying to assess what she had been doing in there. "But we should get her into stasis. No time to help her right now, we've got to get the TARDIS back in shape to go in and rescue—me!"

"First, you get dressed!" Donna pointed a finger at his chest. "Then we get her in stasis. I'll not have you running about naked!"

"Oh, don't like what you see?" He hopped up and walked away, his eyebrow waggled at her and her mouth dropped open.

There was that smirk and sass again! Looks like the Doctor, but definitely not the Doctor! she thought to herself as she did her best to avoid staring at his backside as it rounded the corner to head down the hall to the Doctor's bedroom.

A few minutes later he was back and they quickly and gingerly picked up Scarlett and carried her to the med bay, laying her quickly on a bed. The Duplicate Doctor tapped the controls and a stasis field surrounded her. They went back out and began repairs. A few minutes later, he finished reattaching a light to the interior of the TARDIS walls. He was now wearing a red t-shirt and the Doctor's blue suit. "All repaired, lovely. Sssh, no one knows we're here. Gotta keep quiet."

He began to run around the console, followed by Donna. "Silent running, like on submarines when they can't even drop a spanner, don't drop a spanner!" He spoke quietly, then stopped and smoothed down his suit. "I like blue, what d'you think?"

Donna shook her head at him. "You. Are. Bonkers!"

"Why?" He frowned. "What's wrong with blue?"

"Is that what Time Lords do? Lop a bit off, grow another one? You're like worms!" She was exasperated by all that had happened in the past half hour.

"No, no, no, no, no, I'm unique," he stated matter-of-factly. "Never been another like me. 'Cause all that regeneration energy went into the hand. Look at my hand." He wiggled his fingers. "I love that hand, but then you touched it. "WHAM!"

Donna shrieked in surprise and he put his hands out. "Sssh!" He raised a finger to her mouth, then dropped it and continued, "Instantaneous biological metacrisis. I grew out of you. Still, could be worse."

"Oi, watch it, spaceman!"

"Oi, watch it, Earth-girl!" he snapped back, then straightened in surprise. "Ooh!"

Donna's jaw dropped, again.

He continued, "I sound like you. I sound all... all sort of... rough."

"Oi!" Donna snapped back.

"Oi!" he rattled back.

"Oi!" she raised her voice.

He did it again, he shushed her and started to get annoyed. "Spanners, sssh! I must've picked up a bit of your voice, that's all. Is it?" He put his hand over his chest. "No, still have two hearts. But how is that possible? I thought for sure just now that—" He paused and frowned again. "I would have thought that enough of your genetic material would have passed to me that I would have ended up changed more. Something happened."

"What about what Scarlett did? Before you—materialized or whatever—she touched us both when all that energy was coming off us."

"Oh, then maybe—" He frowned. "Argh, I should know this! It's like I can tell the memory is there, I just can't access it. Like—wait, she was wading about in our minds too, wasn't she? Come on, Donna. We need to check on Scarlett."

(TO BE CONTINUED)