Tova Sullivan, a widow, works as the night janitor at the Sowell Bay Aquarium. Tova is lonely and isolated, but she finds solace in her friendship with Marcellus, a giant Pacific octopus who lives at the aquarium. The novel explores themes of loss, grief, friendship, and the power of the human-animal bond.

Maya Andersson and Benji Ovich, two young people who left Beartown in search of a life far from the forest town, come home and joyfully reunite with their closest childhood friends. There is a new sense of optimism and purpose in the town, embodied in the impressive new ice rink that has been built down by the lake.

Diana and her boyfriend Finn are planning a trip to the Galápagos Islands when the COVID-19 pandemic hits. Diana is stranded in New York City while Finn is deployed to a hospital in Los Angeles. Diana struggles to cope with the isolation and uncertainty of the pandemic, and she begins to question her relationship with Finn.

The novel tells the story of Sam Masur and Sadie Green, two friends who meet in a hospital when they are children. They bond over their shared love of video games, and they eventually go on to become successful video game designers. However, their friendship is tested by fame, success, and tragedy.