Welcome to Dhaka, Bangladesh in 2089. A city notorious for its extreme population density has found an unexpected way to not just survive a global climate apocalypse, but thrive: pump enough biological nanotech into the neighborhood and all of the bodies together form a self-sustaining, and even temperate, microclimate. Of course, this means that millions of humans have to stay put in order to maintain a livable temperature, and people are getting restless. All of the nanotech has also led to some surprises: certain people no longer need food or water while others can live without functioning organs.