It began as another common dream, being at an sf con with supergee. That included odd but essentially realistic events, such as being read a short horror story by the author, a shy man with a bad toupee, and trying not to fall asleep.
Suddenly, up from a lower, underground hallway, came a huge rush of water. People went to investigate, but I saw body parts, including a child's hand, in the water, so I grabbed S. and fled to the glass doors out of the building. As we exited, the entire lobby filled with water behind us. Outside, we and some others climbed up the building walls to the top of a porch and other roof-like structures. (It was fortunately old-fashioned, with lots of gingerbread for footholds and handholds.)
As we caught out breath and looked at the watery landscape around us, we realized the water, as deep as several floors, was full of its own alien, huge and predatory ecosystem, much as in Stephen King's "The Mist," but with aquatic creatures of all sizes. They were more like ordinary animals than in the movie of The Mist, but more often gelatinous. A long sequence ensued of trying to stay out of the reach of the larger animals, precarious footing, and the grisly fate beneath the waves of those who fell. Some small creatures climbed up the walls or pillars, and we kept watch to pluck them off & throw them back in the water. However, just in time we realized that throwing in the smaller creatures was attracting larger creatures right to our area!
Then some of the people who fell in started coming back, climbing up to us, but changed in some unknown but sinister way by the water. We weren't sure what they wanted, but they were determined to do it, and it was nothing good--most likely drag us in so we changed as they had. At first, the main problem was fighting them off. Then, a few times it was hard to tell if someone had changed or not: We didn't want to risk allowing one of the water-changed to get to us, but once we made the other mistake--shooting a regular person who then fell into the water--& that was tragic.
I leave out several plot developments in which my small group of stragglers from the sf con made it to a tower left by construction, and then to an enclosed farm-like area just above the water level. each included conflicts with the people already there, as well as with the hostile ecosystem in the water. We left when the military came into the area by the hotel from the sf con: they might win, but maybe not, and in the meantime the bullets were flying and the creatures were even more aggressive than usual.
At one point, a huge ship went past, larger than a cruise ship, and we knew that the beings aboard were intelligent and were behind the ecosystem, trying to change Earth to wipe us out and remake it into their home: reverse terraforming. There was no confrontation, though, any more than mice would plan a coup against people. We hunkered down and stared in wonder as it passed us, ignoring us.
I'm not sure what the ending was. There probably wasn't any good resolution.
Either before this narrative or interwoven with it were scenes back at the sf con, including a debate/argument by two groups of writers/critics about apocalyptic-crisis fiction and how realistic any upbeat ending was. At the time, that didn't strike me as being as meta as I now realize it is!
Status: well rested for the first time in a while, off to work