Admund can't hear anything on the other side of the door either. He can see that it has been very strongly built, and would take considerable effort to break down.
"Mr Julian could open this," Max says. "Um...the door looks like it was installed fairly recently. Presumably it's here to keep the normal cultists out, since there's no one else down here. It could be dangerous. Still, if Mr Ulrun can open it, we could have a look?"
Max goes with Admund to examine the rubble on the other end of the passageway. The passage is blocked almost completely, and the amount of rubble means that it would take hours to clear even a small path through it. By peering through tiny gaps, it's possible to see that the passage branches off beyond the collapse, with one way heading down and one continuing along at the same level. Nothing else can be seen.
"I wonder what caused this," Max says, "maybe an explosion?"
Looking up though the large hole in the roof, they can see another passage running parallel to the one they are in. "Um, it looks a bit like a sewer," Max says, "a dry section, fortunately! This tunnel must have been too close to a part of the sewers, and something made it collapse. Shall I try to climb up and have a look? I'm the lightest, so I'm less likely to cause it to collapse any more."