Assuming that this rune, too, will be a one-way passage, Kel says to Blunt, "If I don't return straight away, it'll be because this is only works one way. If I can't get back, just stick your hand through. If I can grab it, it means that I can help pull the others up. If not," the lad shrugs, "well, I don't see that we have any other choice. Good luck."
"I hope this takes me somewhere just outside the building. If it doesn't, we might be stepping from the frying pan into the fire."
Drawing his dagger, Kel reaches upwards, preparing to pull himself up.