A/N:Title is from the Sherlock Holmes line: If you remove the impossible, whatever remains, however improbable, is the truth.

It seemed fitting.

Disclaimer: I think it's well established that I own absolutely nothing.

Whatever RemainsGwen & Amanda

It felt like the world was ending. As she continued to stare in mute horror at the screen, Gwen's insides hurt so badly that she couldn't speak, couldn't breathe. But she couldn't look away, afraid that the act would make it real and then all those people would be dead. Ianto would be dead. It felt like the world was ending, and maybe it was.

*-*

Amanda felt completely useless as poor Clem died in Gwen's arms. Despite her Immortality and all the skills and knowledge she had acquired over the millennium of her existence there was nothing she could do against these monsters. Every fibre of her being was telling her to run; to get as far away from London and from Torchwood as she possibly could. But she couldn't, and it wasn't just Jack and Ianto or her newly formed friendship with Gwen that was keeping her there. She actually wanted to stay and try to fix this.

As they turned their attention back to the small screen and the events unfolding in Thames House, Amanda could see the pain wrought on Gwen's face and wished she could do something to allay the agony her friend must be going through but the presence of Johnson and her men prevented her from revealing the truth to Gwen.

Once they were escorted into the back of a blacked out van, alone but for a single guard, Amanda risked offering words of comfort.

"Gwen, listen to me," she said, voice barely above a whisper as she laid a comforting hand on her friend's. "Everything is going to be okay."

Gwen looked up at her, confusion and a little anger in her eyes.

"How can you possibly say that? Yan…" she tailed off into quiet sobs, incapable of finishing the sentence.

"Will be okay," Amanda said firmly. Shocked, Gwen met Amanda's gaze again and Amanda looked intently back, hoping she could see the honesty there and have the sense not to ask any questions.

Gwen was clearly dumbfounded, but she seemed to get the message, just nodding before staring out the window, her face now thoughtful.

*-*

The blacked out van made its way toward Thames House. Outside the city was eerily quiet, the streets deserted in stark contrast to the earlier gridlock. Inside the van, Gwen's mind was reeling. Amanda was so certain that Ianto was okay, it was though she knew something about Ianto or the 456. What secrets was she keeping from the rest of the team?

And then uncertainty gripped Gwen as she replayed the events of the last few days and she wondered if she was the only one in the dark.

Jack had already encountered the 456 once before, he knew more about them than anyone. And Ianto had seemed so confident and unafraid as they left the warehouse that Gwen didn't know what to think about him.

More secrets and lies. Par for the course with team bloody Torchwood.

Once they reached Thames House, they were escorted to a large hall. The air conditioning had been turned on to help preserve the bodies and Gwen shivered as she entered the room. It smelled clinical, of antiseptic and other chemicals Gwen couldn't identify but which she presumed had been used to decontaminate the building.

The bodies of the fallen lay in neat rows, covered with red sheets, and Gwen was reminded of images she'd seen as a child of miners' bodies laid out in church halls after a pit collapse.

There were so many, they needed to be directed to where Jack and Ianto lay, which was funny in a sick way and Gwen had to stifle a laugh as she followed the UNIT officer's directions.

She knelt between them and pulled the first sheet from the face underneath; it was Jack. Gwen released the breath she hadn't realised she was holding and looked up at Amanda, who smiled reassuringly and then knelt beside her and placed a hand on her shoulder.

"I know this must be hard, but they will both come back. I promise," she whispered. Gwen's confusion must have shown on her face because she added "We'll explain everything later, when it's over."

Gwen still couldn't understand, couldn't process the information. She pulled back the other sheet and there lay Ianto, cold and pale and definitely dead. He wasn't like Jack, nobody was, so he couldn't come back. She was about to say this to Amanda when Jack revived behind her.

She only spared him a glance, but it was enough to see a look pass between him and Amanda that confirmed what she already suspected. Whatever was going on here, Jack knew about it, which probably meant Ianto had known too.

Her train of thought was interrupted when suddenly, impossibly, Ianto sat up with a sharp intake of breath. Jack darted forward to grab him into a hug, but Ianto looked at Gwen over his shoulder. She could see shock and guilt on his face for a moment, but then it was replaced by his warm and friendly smile that he used to reassure the public.

Yup, he knew too, she thought. But Amanda had been right about one thing; whatever was going on here could wait. First they had to get rid of the 456.

*-*

Amanda's heart and mind were racing. This was too public, too many watchful eyes were about to witness Ianto revive. If they were lucky, UNIT would chalk it up to whatever they thought was keeping Jack alive. If they were unlucky, one or all of them could be dissected like a lab rat before the day was through.

Gwen's quick steps beside her were strangely muffled and Gwen hadn't said a word to her since the van. The silence was positively deafening. Amanda had no idea what her reaction was going to be to Ianto's Immortality, but she didn't seem the type to take such deception lying down. Perhaps Ianto had been right all along, that honesty had indeed been the best policy in this case, but they had all agreed it was for Gwen's own good to keep her in the dark. It had seemed like a good idea at the time, but Amanda should have known from her own experience that it was hard to hide Immortality in such circumstances. It had been part of her reluctance to join Torchwood the first ten times Jack asked her.

As they approached the place where Jack and Ianto lay, Amanda was relieved to feel the presence of another Immortal. What the 456 had done was completely out of her realm of understanding and she had been worried that they'd somehow killed Ianto and Jack permanently. Whatever they had done, it was taking both men a very long time to revive; it must have seriously damaged their bodies.

Gwen kneeled down and pulled back one of the sheets covering them, revealing Jack's face. She let out a breath and looked up at Amanda. Feeling she needed to reassure Gwen, she smiled and then kneeled down so she could put her hand on Gwen's shoulder.

She checked that they were out of earshot of the others in the room before repeating her assurances that Ianto would be okay, and promising that Gwen would get her answers, just not yet.

First they had to eliminate the bastards who had filled this room.