It is misleading to call Make Room, Make Room! a post-apocalyptic narrative, because there's not really an apocalypse at any point. Nor *technically* can it be an alternative future, as it's set in the world that we occupy. Also because technically it's set in the past. We'll go with dystopian future.
Written in 1966, Harrison predicts what life will be like for the 334 Million inhabitants of New York City, in the year 1999. It's a grim and desperate place, overcrowded, filthy and full of misery. Most people live in abject poverty, those that have a roof over their heads share their rooms with many other families, food is strictly rationed and water is collected from taps in the street between certain times. There's a feeling that the environment is doing everything it can in revenge for the toxins and the pollution that humanity has inflicted on it. The sun's heat is much more intense in the future, and everyone swelters in 40 degree heat in the summer, then freezes in the winter. There is no electricity, gas or natural resources of any kind. There are no cars on the roads, only peddle cabs. The cars are now homes, rusting away in useless car parks.
The plot switches between several New Yorkers, as we witness the events in NCY between the Summer of 1999 and the eve of the 21st century. NYPD Police Officer Andy Rusch shares a single room with retired engineer Sol, who has wired up a wheel-less bike to power their fridge and TV with home-made power. Andy likes his job, but the pay is rubbish, the hours are ridiculous and it's pretty pointless having a homicide department in a city where there are hundreds of murders a day, and a single department to deal with it. We also meet Billy Cheung, who loots a food store during a Pensioners' riot, for a box of luxurious soylent steaks (a delicious sounding meat substitute), selling them to fund a job as a messenger. Actual meat just isn't obtainable any more, most people seem to survive on algae crackers and oatmeal. Their paths meet when Billy accidentally becomes a wanted criminal, something which is suspicious in itself, in a city where the crime rate is too high to keep count of. Shirl, girlfriend of a murdered crime syndicate who lives in an air-conditioned apartment with plumbing (!) is also a central character, the only one perhaps that has a vaguely comfortable lifestyle and who is forced by circumstances relating to both Andy and Billy to experience a different life on a different social plain, even if only temporarily.
It's relentlessly bleak, focusing on a lack of natural resources, unsustainable urban development/decay and overpopulation as the world's undoing. It's implied that birth control is 'just not done', it seems odd to Shirl at least, we assume for socio-religious reasons. Though there is no other religious leaning in the book, save for the prophet of doom that appears towards the end, predicting the end of the world at the stroke of midnight. It's not a particularly riveting narrative, it took upwards of two weeks to read, despite being short. The hostility of the world prevents characters behaving in a way that However, it raises some interesting ideas about the worlds (still) increasing population and the reactions of civilisation to the challenge and impossibility of attempting to live in a world that is exhausted and can no longer support the human race.