Content Warning: The source material features graphic depictions of sexual assault, violence, neglect, and cruelty to animals.

On the 25th floor of a high-rise outside of London, Dr. Robert Laing roasts the Alsatian dog of the building’s architect and penthouse resident, Anthony Royal. When Laing moved into the building six months prior in search of solitude and anonymity, there was no sign of barbarism latent in its middle-class residents; nonetheless, barbarism soon consumed the building. As he eats Royal’s Alsatian, Laing realizes the harbinger of this chaos came three months prior, on the day the building reached capacity.

That Saturday morning, a bottle of imitation champagne explodes on his balcony. Looking up at the vertiginous face of the building, Laing is annoyed that no one from the party floors above noticed the falling bottle.

Laing tries to forget about this affront as he arrives at another party thrown by his upstairs neighbor, Charlotte Melville. Despite his efforts to distance himself from his neighbors, Laing soon finds himself drawn into their petty disputes. Charlotte probes Laing for his opinion on the 31st-floor residents—the source of the exploding bottle. No matter their position in the high-rise, residents find reasons to criticize the people above and below them.