Ianto shook his head. "Nope. They're not. There's...a complicated explanation to it all, but I don't really understand it myself, so here's the shortened version. There's some sort of a perception filter on this spot. It makes it so that even if people notice us, they don't really notice us. We could be doing whatever we liked on this spot, yelling, being obtuse, whatever, and they'd all be none the wiser. Only on this one slab, though." He smiles. "Invisible Lift, I named it. I think it has a nice ring to it, don't you?"