Leave the World Behind explores themes of race, class, parenthood, environmental devastation, and dependency on technology against the backdrop of a mysterious disaster of potentially apocalyptic scale. The title of the book, Leave the World Behind, works on several levels to convey the novel’s themes and central ideas. The phrase comes from the Airbnb description of the vacation house and conveys the property’s remoteness as a desirable attribute. But once all electronic communication ends and the two families lose contact with the outside world, the phrase takes on a more sinister meaning. It signifies how isolated the house and its inhabitants are, which makes it impossible for them to get any information about what is happening. As it becomes clear that the New York blackout is only the beginning of an event of world-ending proportions, the phrase acquires a new meaning entirely. It conveys a sense of permanence about the disaster, making it clear that none of the characters can go back to their previous lives. The world they knew and understood is gone, and these two ill-matched families might be isolated together permanently, as they try to survive as an unlikely community.  


When G. H. and Ruth first arrive, Amanda and Clay are thrown off-balance by their own confusion about whether they are hosts or guests. They are also confused about how to behave around wealthy, well-connected New Yorkers who happen to be Black. Amanda’s inherent racial bias makes her suspect G. H. and Ruth of being con artists. While Clay is less racist than Amanda, he shows his own racism when he excuses himself for being bad at recognizing Black faces. G. H. and Ruth have years of experience with defusing racist preconceptions. They put on a performance carefully designed to allay the suspicions of frightened white people. Even so, Amanda continues to be skeptical. The war between Amanda’s racism and her respect for wealth plays out in almost comical ways as she is forced into social situations with G. H. and Ruth. Clay, on the other hand, has his sights set on the cash refund G. H. offers for the inconvenience of letting them stay. Even though G. H. and Ruth prove their ownership of the house in all kinds of ways, Amanda and Clay don’t even consider giving up their temporary right to occupy the master bedroom. They paid for the illusion of ownership, and they feel entitled to get what they paid for.  


All of the characters show signs of withdrawal from their devices, but the one who suffers the most without access to his phone is Clay. Alam suggests that people have become accustomed to relying on external tools in place of knowledge and skills that used to be internalized. Without access to his GPS, Clay is unable to retrace a simple route into town. By contrast, his thirteen-year-old daughter, Rose, is able to navigate her way through the pathless woods with no difficulty. This difference is significant, indicating that Rose is more adaptable, and therefore more likely to survive than her more experienced father in a world stripped of all technological crutches. While Amanda relied on emails from people at work for a sense of self-worth, her need for validation fades in the face of the crisis. The only thing Ruth misses about her cell phone is her ability to contact her daughter, but G. H. is acutely affected by the loss of access to instantaneous information to explain things. The crisis has stripped each individual right down to the bare essentials of what they know and what skills they possess without a smartphone in their hands.  


The terrifying noise overhead creates a turning point in the novel, interrupting the awkward poolside small talk of Amanda, G. H., and Ruth, and blasting away social differences to unify them in fear and disbelief. From this point on, the adults in the group are forced to lay aside their reservations about one another in order to band together against a common enemy—fear of the unknown. Setting aside her ingrained racism, Amanda looks to Ruth and G. H. for support and guidance as she and Clay strive to cope with Archie’s mysterious illness and Rose’s disappearance. Ruth, despite her reluctance to feel empathy for these strangers, can’t help but sympathize with Amanda, not just as a fellow mother, but as a fellow human being. Their common experiences as parents bind them together in a bid to protect the children from a dangerous and unpredictable world. In the aftermath of the noise, an unseen hairline crack in a pane of glass signifies the literal shattering of the world as they know it.  


While brief passages of omniscient narration give us little reason to hope for a happy outcome, Rose’s self-appointed rescue mission hints that there will be some survivors who reshape and rebuild human society. Early in the novel, Rose is presented as the weakest and least aware character, as she nags her parents to fix the internet and distracts herself from boredom by baking a cake. However, she is the first to notice the crack in the glass door, and the first to acknowledge that the family’s vacation is over, and that all of them are now living in an unfamiliar, dangerous reality. Even though the adults try to conceal their panic, Rose senses the magnitude of the disaster by paying attention to the natural world. Her strength lies in her ability to accept what has happened as fact and to move on by taking constructive action. The motivations for her rescue mission are ambiguous: she may be pretending to be the hero of one of her books or trying to prove herself to her family. Nevertheless, Rose is the only one who faces the crisis with calmness and a faith that the world still holds value. The novel concludes with Rose’s chilling reminder that any ordinary day has the potential to end in tragedy.