So here we are, all together deep under the Earth. The only way for us to go forward is to use a large quantity of explosives on the cave in front of us. Uncle lights a long fuse, and we wait on his raft for safety. But disaster! The explosion causes the cave floor to collapse! It opens a channel for the sea to rush down!
The underground sea makes the hole bigger and bigger! We are pulled with the cavern! Faster and faster we plunge downwards!
We must have fallen at a hundred miles an hour! We can barely hold on! The noise is deafening! It is a miracle that we are not smashed to pieces against the walls!
After what feeels like an eternity we finally come to rest. Shaken, bruised, soaked, terrified, exhausted
We can hear the lapping of water against walls in all directions : we must be in some kind of circular cavern. My guess is a vertical lava tube. If so, we cannot be far above the Earth's natural magma. This violent rush of water, when it hits the hot rocks, would expand below us and probably trigger a volcanic eruption, and we're right on top of it with no way out.
After a while I think I can see two large animal eyes in the darkness. They face forwards, indicating a large predator. It must be some kind of cave. Should we take our chances with the beast? Or stay on the raft and wait for the volcano to explode? Or do something else?