There are pathways, yes. That is why I took your little glasses from you while I was convincing you not to go. Imagine if that wall turned black while you were inside.

[He shakes his head; let's not think about that, actually. It makes him faintly uncomfortable... BB still isn't back. She might be stuck.]

Not that I knew it would at the time, but you can thank me later for my intervention, Doctor. [Grins at him... yes he's messing with you, Add.] I realise what you want to do is important, but you're smart enough to know you shouldn't walk in blindly and expect to come out in one piece. There may be ways to protect yourself, though.