Tova Sullivan is newly widowed and alone. She lost her 18 year old only son many years ago in an accident at sea in what many assumed was a suicide, although Tova refuses to believe that conclusion. She has a few remaining friends but she doesn't share much personally with them, hating to feel obligated or dependent or pitied. Although she does not need the money, she works several evenings a week as a cleaner at the local Sowell Bay aquarium. She is absolutely meticulous in her work. Her life is quite circumscribed and lonely and she is determined not to rely on anyone else, making plans for her future that she shares with no one. One night, while cleaning, she discovers Marcellus, the Giant Pacific Octopus, out of his tank, tangled in electrical wires. She returns him to his tank and they become friends of a sort. He recognizes something of himself in her. He is literally a captive in his tank (aside from when he escapes) and she is a captive in her solitary life.
Cameron Cassmore has been adrift in his life for a while. Raised by his aunt after his struggling mother left him, he is 30 and can't seem to hold down a job or keep a girlfriend. He is very definitely a lost soul. When his aunt gives him a box of his mother's things, he discovers a class ring and a photograph that might lead him to the father he's never known. There's nothing holding him where he is so he heads for Washington State to confront the local developer he is convinced is his long unknown father. Cam ends up filling in as the aquarium's evening cleaner after Tova has an accident that leaves her unable to walk for a bit. It is here, in front of Marcellus' astute gaze, that Tova and Cam's stories cross and Marcellus is determined that the knowledge he has of the night that Tova's son Erik was lost at sea and the observations he's made recently must be passed on before his own short time is up.
The novel is mostly told in third person, focused on Tova and then focused on Cam, but there are first person chapters narrated by Marcellus, which gives the reader much more information than either of the two main human characters have. And Marcellus as a narrator is charming and funny and smart and just a little bit irreverent. His chapters start with his age; he always knows that he is quite elderly for a Giant Pacific Octopus. He is probably the most self-aware octopus in all of literature. Tova is matter of fact and stoic but also closed off from the people in her life who very much want to care about her. She thinks she's just an obligation to everyone when in fact she is far more than that, if she'll only let them in. Cam is decades younger but similarly stuck in life, feeling unmoored and left behind by his closest friends. As the story unfolds, there aren't any surprises for the reader but that isn't really the point of the novel anyway. It is more about Marcellus being able to break through the grief and loneliness of these two people who have no one and give them the truth they each need and want to move their lives forward. It is a heartwarming story of family, found and blood, and staying open to others, to love, and to the joys still to come in life, no matter how short or long that life may be.