All human life is confined to huge domes that are half flooded, and where people cling to floating debris. Many suffer from strange fungal diseases. Death is only a matter of time.
Myself and a few companions manage to scale the interior of the roof of the enormous dome where we smash a hole and crawl out on to the surface. We then slide and role for hundreds of meters down to the ground. There we find a vast abandoned city.
The land is dry, unlike the flooded interior of the dome. But some terrible presence is watching us. The same terrible presence responsible for our confinement in the dome. We must hide. When we fall to the earth outside the dome we unbalance a large ancient stone column. It falls and collides with the door of a nearby building.
The door is opened and we can enter the building and hide there. Now that we are inside the city complex we can move about undetected.