The Doctor flew to Ianto's side. He wrapped an arm around the man's throat and clamped a hand tightly over Ianto's mouth, effectively cutting off his airway. Not knowing what was going on, the Welsh man kicked and fought as the Doctor drug him back towards the TARDIS door.

"What the hell is going on!" Jack yelled.

"Virus," was all the Doctor managed to say before Ianto went lifeless in his arms.

"Action has been taken," the 456 said in the same monotone voice. "You wanted a demonstration of war. A virus has been released. It will kill everything in the building. Now the remnant will be disconnected." A high pitched noise came bursting from the speaker just as the Doctor managed to drag Ianto into the TARDIS and slam the door shut.

A loud, high pitched, whinging noise filled the air of the warehouse. Clem collapsed to the ground clutching desperately at his ears. "Turn it off," he managed to scream through the pain and then he just continued screaming.

Gwen fell to her knees next to the man and Rhys joined them. "What's happening?" he demanded.

"No idea." She pulled at the hands of the elderly man, trying desperately to get him to look at her. There was blood pouring from his eyes and nose. The noise changed pitch and Clem stopped screaming. He stopped screaming, and breathing, and living. Whatever that noise was, it had killed him. A few tears escaped Gwen's eyes. After everything that had happened to this man, he didn't deserve for things to end like this. Her only consolation was that maybe, hopefully, his suffering was at an end.

Rory flew towards the door and helped the Doctor haul Ianto towards the med bay. "What happened?"

Taking a deep breath of clean air, the Doctor said, "They declined my offer to let them leave peacefully. I'm afraid that Ianto has stopped breathing but I don't think he had a chance to inhale the virus." They had reached the door and the Doctor pushed it open. Together he and Rory set Ianto on an examination table. "Let's get him breathing again and make sure the virus hasn't invaded his body."

Rory looked up at the ceiling for a brief moment. "Right," he mumbled. "I have an idea. Stay here, help Ianto and start on the antivirus. I'll be back in a flash."

Jack had raised the alarm and had all of the people in the building clambering towards the exits. But Thames House was designed to withstand a biological attack. Nothing could get in or out. The people were trapped inside with a fast-acting, deadly virus. Rory landed the blue box in the middle if the lobby and set to turning knobs on the console, extending the protective field of the ship to its limits. He wasn't sure if this virus had made its way down this far, or how much good this would do, but it was their best shot of helping those poor people. Especially the ones that had already inhaled the virus. For those people, if they couldn't synthesize the antivirus in time…

The TARDIS groaned at the strain of purifying the air within her protective field. "I know it's a strain, but thank you." Rory patted the console and she hummed back, not able to respond back with their normal telepathic communication. There was no time to lose and Rory sped down the corridor to the med bay.

Inside there was a steady beat of a heart monitor pinging away near the bed Ianto was lying on. The Doctor was hunched over a monitor. "Is he…" Rory started. "Did Ianto get infected by the virus?"

The Doctor's eyes flicked to the Welshman. "No, I got him out of the room in time. He's just unconscious, that tends to happen when someone cuts off your air supply." He pointed at the screen. "Look at this virus. It's beautiful, it'll kill a human stone dead in five minutes but it is a thing of beauty. It would, probably, even manage to give me a case of the sniffles. Impressive, considering my superior biology."

Rory rolled his eyes. "Wasting time, Doctor. Antivirus?"

"I've got the basic structure worked out, but if they've already been affected it may be too late. Like I said, highly aggressive and I'm not sure that once they're infected we can stop it."

"Doesn't mean we won't try." Rory elbowed the Doctor. "Budge up; I need room to work, too." He didn't miss the proud smile the Doctor gave him before they began addressing the problem at hand. There had been a shift, for the better, in their relationship in the past few days. Rory, for one, was very happy about that.

"Are you happy now?" The Prime Minister stared daggers at Rose. "Your friends accomplished nothing except getting people killed. What now?"

"Two choices," General Pierce began. "Either we go to war against an enemy we can't beat, or we go to war against our own people, for their own good."

"Or you shut your mouths and still let us handle this," Rose snarled. "Yes, this wasn't the outcome we wanted but the 456 have had their chance. They could have left peacefully. Now they have brought what's going to happen on themselves. And just so you know, if you hand over a single, solitary child you will live to regret it."

Rose stood and turned to Hannah and the Colonel. "We'll be in touch."

And with a flash of light, Rose Tyler vanished from the Gold Command room.

A bald cabinet member, Hannah thought his name was Yates, started speaking. "I don't care what that woman or the Doctor say they can do. It's obvious that their attempts have failed and we have no choice. We have to hand over the children."

"That would not be advisable," Oduya said quietly but forcefully. "UNIT will still stand behind the Doctor, and I'm sure that many of the other world leaders would rather give him a chance to fix this rather than hand over millions of innocent children."

He stood and motioned for Hannah to follow him. "Mr. Green, I warn you that if you continue with your plan, then UNIT will be forced to take action against you." Then he turned and Hannah followed him out of the room.

Once in the hallway, Oduya rounded on her. "I should have you court marshaled for this. You were given a direct order to tell me immediately if you had contact with the Doctor or Harkness. You made me look like a fool in there."

Hannah opened her mouth to speak but he cut her off. "And don't think for a minute that I didn't catch it. Tyler… Rose Tyler…Patricia Tyler and her husband Anthony Tyler. There's a connection. I know it and I intend to find out exactly what Captain Tyler's connection to that woman and the Doctor is."

"And if you're smart, sir, you would stay as far away from that connection as possible." Hannah hissed. "Because you won't want to find out what happens to people who try to exploit my daughter's connections."

"Is that a threat?"

"No sir. Just a bit of friendly advice." Hannah smiled, turned on her heel and walked away.

A few hours later, Gwen, Rhys, Hannah and Rose had joined the Doctor, Rory, Jack and Ianto in the TARDIS. A heavy silence filled the room. This was the last calm before the storm, the point where everyone knows what's coming but they haven't taken the final step yet.

However there was some good news, despite the close call. Ianto was going to be perfectly fine. Yet after a celebratory 'we're still alive hug' between the men when they had collected Jack's body from the makeshift morgue at Thames House, Jack had made sure to keep at least a person or two between Ianto and himself.

Clem had died, and all in all, 47 people had died from the 456's virus. It was a far cry from the hundreds that would have died had the TARDIS not been there, but it was still unforgivable. There was no way that they would have been able to stop an altered strain of the virus, should the 456 chose to release it. A similar virus would be able to wipe out the entire population of Earth within a day's time. This had made them realize what kind of creature they were dealing with and what options they actually had.

"So what now?" Ianto asked, breaking the silence.

"Now we end it," Rory answered, none too cheerfully.

"How?" Rhys asked.

"We find a resonate frequency that we can use against the 456," the Doctor replied dryly before he moved to the console. "It may take us a while to find the correct one. We had better get started before we either give the government an excuse to hand over the children or the 456 to kill every human on the planet."

"Clem," Gwen said suddenly. "Can we use the same frequency they used to kill Clem against them?"

The Doctor looked pensive. "That might work. Do you have a recording of it?"

Gwen held up her laptop. "Yeah, it's on here."

Jack snatched it from her hand and walked over to where the Doctor was standing. "Excellent, this may be just what we need." Ianto hovered nearby, offering his help where he could.

"And then what?" Rose asked with a small hint of anger in her voice. "We use Jenny or Rory as a transmitter? It could kill them. I can't… We can't…"

"Mum." Rory came up and put his hand on her arm. "I'll be fine. If we use yours, the Doctor's and both TARDISes' shields, I'll be fine."

"I can't lose you or your sister," Rose said softly. "There has to be another way."

It only took a moment for the Doctor to step over and wrap Rose in his arms. "I will never let anything happen to any of your…our children or grandchildren. I'll monitor every aspect of what's going on inside Rory's head and at the first sign of trouble we'll stop and find another way." He tipped her head up so he could look into her eyes. "I promise you that Rory will be fine."

"Ok," Rose said, wiping a few unshed tears from her eyes. "Let's kick some 456 arse."

The Doctor squeezed her tightly and dropped a kiss into her hair. "That's my girl."

It was early evening by the time they had moved the second TARDIS into Ianto's sister's backyard. The majority of the rather large group of people had departed into the Tyler family TARDIS, leaving only the Doctor, Rose, Jack, Jenny, Rory and Amy in the other console room. Rory had wanted Amy to wait with everyone else, but Amy had told him that she wasn't leaving him. They were in this together or not at all.

Rory sat in one of the chairs on the raised platform, diodes and wires attached to his head. He focused on breathing in and out, not on thinking of how dangerous this was.

"Are you ready?" the Doctor asked, squeezing his shoulder. Rory nodded and the Doctor began to ramble out the plan for the umpteenth time. "So, here's what's going to happen. We've got you connected to this TARDIS, which is connected to yours. Your mum and I will be here to help bolster your shields and Jenny and Jack will be monitoring your brain activity. If you go above the designated safe area, Jack will shut everything down."

He clapped his hands together. "Now I don't think that we have to keep you connected for long. You just need to connect to the same brain waves the 456 were using on the children, set up the resonate frequency and let the children of Earth do the rest. Any questions?"

No one said anything, but Amy stepped forward and grabbed Rory's hand. "I love you to the ends of the Universe."

"And back again," he finished as she leaned down and kissed him. Pulling back, he said, "I'll be fine. I promise."

She punched his arm and smiled. "You'd better." Then she stepped back to stand by Jack.

Rory closed his eyes tightly. "I'm ready." He heard the clicks on the keyboard from Jack and felt the Doctor's fingers press into his right temple and his mum's press into his left. His whole body tingled with electricity as he reached out his mind to seek the telepathic link between the children that the 456 had established.

Sweat beaded on his brow under the pressure of the connection that he had found. "Got it," he breathed out and once again he heard Jack typing on the laptop. This time, he was feeding Rory the frequency he needed to end this. The Doctor's fingers were pressing so tightly that Rory was sure there would be bruises later. The high pitched squeal that had killed Clem now filled his head and somehow he knew that all over the world, every child began to wail.

Now that it had begun, Rory knew that he could safely disconnect. But then he heard another sound, a distant howl in the back of his mind. It was powerful, yet familiar and comforting, as if it was always there in the background and yet he hardly ever noticed it. Letting go of the screech, his mind latched onto the howl.

A feeling of peace and protection washed over him. The pressure on his left temple increased and a second howl joined in, slightly higher in pitch than his. It was as if they were singing an ancient and powerful ballad. The fingers on his right temple twitched before quickly being removed as if the fingers of the owner where singed.

Through a hazy veil Rory heard someone yelling, "What's going on?" and another astonished whisper of "Bad Wolf." But right now, the people behind the voices didn't matter. Rory focused on tracing the link back to the creatures that had caused all of this. He and the wolves howling in his head reached out to find the ones that had panicked helpless parents and had used innocent children for their own nefarious intent.

He found the connection to the one in Thames House as well as to the ship, hiding, well-disguised on the outskirts of the solar system. Without conscious thought, he poured the power of the wolf howl into all of those creatures. And molecule by molecule, atom by atom, the 456 were pulled apart in a haze of golden light and the children of Earth were once again safe.