The Life Cycle of the Common Octopus

Emma Knight’s debut novel, The Life Cycle of the Common Octopus (2025), follows a year in the life of Pen, a young Canadian studying abroad in Edinburgh alongside her childhood best friend, Alice. Pen and Alice begin to leave their childhoods behind as they navigate the complexities of friendship, romance, and heartbreak. Meanwhile, Pen also befriends the aristocratic Lennox family (university friends of her father’s) and attempts to find out why her parents’ marriage fell apart and what happened between her father and the Lennoxes many years ago.

The novel was a New York Times bestseller and a “Read with Jenna” Book Club Pick. The Life Cycle of the Common Octopus explores The Sacrifices of Motherhood, The Importance of Female Friendships, and The Transition from Adolescence to Adulthood.

This guide refers to the eBook version of the 2025 Penguin Publishing Group edition.

Content Warning: Both the source text and this guide contain descriptions of pregnancy loss, sexual violence, and suicidal ideation.

Plot Summary

An adult Penelope Elliot “Pen” Winters, having recently given birth to a daughter, looks back on her first year of college and recalls it as the time when she began her adult life.

The narrative shifts back in time to 2006. In this earlier era, Pen and her best friend, Alice Diamond, leave their hometown of Toronto to begin their first years at the University of Edinburgh. Alice intends to study acting, while Pen is studying English and French. However, Pen’s real motivation to go there is to follow in the footsteps of her father, Ted Winters, who attended the same university years ago and befriended Lord Elliot Lennox, who is now a famous mystery writer. Ted later had an unhappy marriage with Pen’s mother, Anna, and the relationship ended in divorce. Now, Pen suspects that the key to their unhappiness is a secret of her father’s that she might discover in Scotland.

At school, Pen and Alice quickly befriend other students, including Jo and Fergus Moore, wealthy twins from a Scottish family, and Charlie Watson, who is infatuated with Alice. Pen writes to Lord Elliot Lennox and is invited to his home for the weekend. At the Lennox estate, Talmòrach, she meets Elliot, his wife Christina, and their eldest son Sasha. Christina is a warm, welcoming hostess, and Pen feels immediately attracted to Sasha. Although Elliot is kind and jovial, he is not forthcoming about Pen’s father. Also in residence are Sasha’s best friend, Chet, and Elliot’s niece, George, who has a baby son named Danny. After the weekend, Chet and Sasha return to nearby St. Andrews, and Pen resumes school. She chats online with Sasha and begins a flirtatious relationship.

Though Pen does not discover this until later in the novel, Ted once had an affair with Elliot’s younger sister Margot, who is now a famous fashion designer. George is their daughter, but Margot never wanted to marry and urged Ted not to return to Scotland. The Lennoxes quickly realize that Pen is unaware of this connection, and they want to be friendly to her, but they also hope that her father will be the one to tell her the truth.

Meanwhile, Alice is cast as one of the leads in a school production of Tom Stoppard’s Arcadia, but she is distracted from her work by Julian Sachs, her handsome philosophy tutor. She and Julian embark on an illicit affair, but Julian is possessive and prone to power plays, frequently objectifying Alice. Although Pen and Jo suspect that Alice is sleeping with Julian, Pen says nothing because she is worried that Alice will feel judged.

Sasha invites Pen up to Talmòrach, telling her that he will meet her there after his polo game. When Pen arrives, Christina tells her that Sasha has been delayed by a rainy start to the game. The weekend quickly becomes awkward when Pen accidentally discovers the younger Lennox son, Freddie, hiding in his bedroom when he is supposed to be on a gap year in South America. The family does not explain why he is there or even acknowledge that he is in hiding. Meanwhile, Sasha arrives late, and Elliot inadvertently reveals that the polo match was cancelled. Realizing that Sasha deliberately avoided her, Pen leaves early, feeling that Sasha and the Lennoxes resent her presence. Upon returning home, she is surprised and delighted to find that her father is waiting for her. He tells her that he was on a business trip to London and came to visit. Although he takes her to dinner, he won’t give her any more information about his past with the Lennoxes.

Saddened by Sasha’s rejection, Pen becomes increasingly isolated, a situation that is worsened because Alice is busy with Julian and is avoiding her. Pen finishes her exams and looks forward to spending winter break at home. Before she leaves, she decides to return the flirtations of a student named Fergus, who has been awkwardly trying to pursue her. After a school function, the Pen and Fergus go back to his room to have sex. However, when they are interrupted by some drunken friends, Pen realizes that she doesn’t want to sleep with Fergus after all. He is unable to maintain an erection after the interruption, so she takes her leave, relieved but not realizing how embarrassed he is.

Alice spends the winter break in Mexico with her family and regrets the her growing emotional distance from Pen. She is also increasingly disenchanted with Julian; when she discovers a photo on Facebook of him and his pregnant wife, she decides to break up with him.

Meanwhile, in Toronto, Pen is relieved to spend time with both of her parents. She enjoys being with her mother, Anna, who became a professor and has lived a full life after her divorce from Ted. During Pen’s childhood, Anna had depression and nearly died from an overdose of sleeping pills, but Anna is no longer unhappy. Pen tells Anna about the Lennoxes, and her mother explains that that part of the past is painful for her. She tells Pen that she had several pregnancy losses during that time, one of which occurred when Ted was spending time in London for work after college. She explains that they initially chose the name Elliot for the son that they lost, but they gave this name to Pen as a middle name when she was conceived. As Pen leaves for school, Anna gives Pen her diary from that time period, telling her that it will answer her questions.

Pen feels able to put the past to rest for now and decides not to open the diary. She is also distracted because she and Sasha have resumed texting and chatting. When school begins, Julian sexually assaults Alice in an empty lab room, refusing to believe that the affair is over. Alice immediately tells Pen, who devises a plan. She flirts with Julian and gives him her number, correctly surmising that he will flirt back in order to take revenge on Alice. She, Alice, and Jo use the texts to manipulate Julian into sending them sexual photos, which Pen then takes to the university.

As a result, Julian is fired, but Pen’s reputation on campus is also ruined. Many students assume that she is the one who had an affair with Julian. Several people leave lewd magazines at her door and write posts about her online, including Fergus, who is still hurt by their failed liaison. However, Sasha knows the truth and invites Pen to come home with him for Danny’s first birthday, promising to explain why Freddie was hiding at the house.

Over the weekend, Pen meets Elliot’s younger sister Margot, who is cold to her although the rest of the family greets her warmly. Freddie explains that his cousin Hugh, who now works in the Diplomatic Service, made his life miserable at school. Freddie and a friend began a series of pranks in which they mailed random items to Hugh at work. However, they miscalculated when they were on a beach and sent him an envelope of sand. Unbeknownst to them, the office assumed that they had mailed a biological weapon. Christina managed to convince the government that Freddie should receive no greater punishment than a fine and community service. Freddie is currently paying the fine by working for Margot in her London office.

Sasha and Pen have sex for the first time, and she is happy to finally be in a relationship. However, when they are cuddling, they talk about his family, and he mentions that George’s father abandoned Margot and went off to America. This comment, coupled with Elliot’s earlier remark that Ted fancied Margot, makes Pen realize the truth. She waits until Sasha is asleep and then goes back to college.

When she confronts Ted over the phone, he initially makes excuses but finally agrees to be truthful with her in the future. In Anna’s diary, she finds a letter from Margot to Ted, telling him the news of her pregnancy. Other entries describe Anna’s desperate desire to be a mother and her laments that Ted’s family did not like her. When Pen calls her mom, Anna explains that the overdose was an accident and that she would never abandon Pen. Anna is not sorry that her marriage ended, but she has never regretted being a mother. She explains that she was raised by foster parents who did not love her, and she has never wanted to make Pen feel unloved.

Elliot visits and gives Pen Margot’s number, telling her that she is welcome to visit with them anytime. Pen meets Margot at the National Aquarium, and the older woman tells her not to blame Ted. She compares motherhood to being an octopus that is eventually devoured by its young. She explains that she didn’t want to life a self-effacing life and does not mind being deemed selfish for raising George unconventionally. Pen also visits George, who welcomes her and explains that she doesn’t miss or resent Ted.

Pen reconciles with Sasha, and they agree to begin a real relationship. Alice’s play goes well, and she begins to date her friend Charlie. That summer, Sasha takes Pen back to the estate, and Christina greets her warmly, offering a different perspective than Margot’s on motherhood. She tells Pen that she is happy and freely chose her life. Sasha helps Pen to clean out her freshman dorm; Pen plans to return next year and share an apartment with Alice and their mutual friend Jo.

In the epilogue, an adult Pen holds her daughter and reflects that she will set down these memories as stories for her daughter to read if she ever wants to.