"There was a moment, one magical moment, when you could see us all floating in mid-air halfway up our living rooms, upside-down in whatever pose we had been in at the time -- coffee drinkers drinking coffee from inverted coffee cups, lovers clinging to each other's falling bodies, old men groping for slipping hairpieces, children crowing and cats screeching, all of us surrounded by the asteroids of our possessions."
That's pretty much the whole story, right there. Gravity is reversed (though inconsistently -- how can you drink coffee if it's floating away from you?), and the narrator, Toby, is trying to get to his ex-girlfriend Sophie to return her goldfish. Unfortunately the story is much too long for this slight conceit, and a lot of this length is given over to description. "I scrambled up and worked my way through the tumbled-over living room, over the knee-high threshold into the corner." (Okay, yes, things are upside-down.) "And so I held on to the playground fence. Tightly! We had reached it by climbing through the walkway door and over the tabletop bridge…" (Upside-down. Right.) "We had climbed on the underside of the bridge, now suspended below the river…" (Yes, we get it already, really, you don't have to remind us.) The story would work much better at about half the length.
That's not the worst problem here, though. The worst problem is that about a third of the way through I began to realize that Toby is a horrible, horrible person. He's so intent on rescuing the goldfish he lets a woman die. At the end, when he finally finds Sophie, she has a broken knee and a hurt back, but he's fixated on holding her, even though she has to be in terrible pain -- and even though she's already told him, several times, that she wants to break up with him. He seems to think that bringing back the goldfish ("after everything I've been through," he says) entitles him to stay with her, and he's angry when she doesn't see it that way.
When he lets the woman go and saves the goldfish instead, he thinks, "At the end of the world, it's every man for himself. You taught me that, Sophie." And this is so creepy. It's the logic of the abuser -- look at all the horrible things you made me do. It seems to be the logic of this story, too. Near the end, Toby says, "I think I want you to know that you hurt me so incredibly, Sophie." For God's sake, why? Let it go already.