The following version of this book was used to create the guide: McConaghy, Charlotte. Migrations. Flatiron Books, 2020.

Charlotte McConaghy's Migrations is told from Franny Lynch's first person point of view. Though the novel shifts frequently between past and present, the entirety of the narrative is written in present tense. The following summary adopts a linear pattern of explanation, beginning with Franny's childhood.

Franny Lynch, born Franny Stone, grows up on the coast of Ireland with her mother, Iris Stone. Not long after her mother had Franny, she left Franny's father, Dominic, and moved back from Australia to her homeland in Galway. Though Franny is curious about her father, she knows he is a murderer, and is content to live with her mother. Iris, however, is restless and lonely. She tells Franny if she does not stop running away, as is her habit, she will leave her. Franny ventures out with a friend anyway, days later realizing her mistake. When she returns home, she finds her mother hanging from a tree. She spends the rest of her childhood in Australia with her paternal grandmother, Edith. Franny does not like Edith, believing her cold and unloving.

Years later, Franny continues her wandering, unable to stay anywhere for long. She eventually begins working as a janitor at the National University of Ireland. Here she meets the young professor, Niall Lynch. The two fall in love, and marry only weeks into their friendship. Franny feels he is the only one who really understands her. However, as their relationship continues, she realizes she cannot keep her true self from her husband. She leaves him often, unable to remain stationary even on his behalf. A few years later, Franny gets pregnant, but their daughter is stillborn. Her death troubles both of them. Though this grief is unbearable, Franny is even more devastated, when Niall says they should break up. Frantic, she crashes their car, killing Niall.

While in prison, however, Franny does not remember what has happened. She is convinced her husband is still alive. Eventually she gets released on parole, and moves in with Niall's mother, Penny. Penny tells her Niall wanted his ashes scattered where the Arctic terns fly. Franny breaks her parole, takes the ashes, and travels to Greenland. Here she tags several terns with trackers, and convinces the fishermen of the Saghani vessel to allow her onboard.

Though the fishermen are skeptical of her mission to follow the terns to Antarctica, their captain, Ennis Malone, agrees to help. In time, they all become friends. During a storm, one crew member is struck by a cable, and dies. Franny helps revive him, and the crew lands in Newfoundland. While staying in town, the crew learns that all commercial fishing vessels have been recalled. Not long later, Franny stabs a man in the throat after he attacks her. The crew flees back to the water, despite the sanctions.

Though they know they are in danger, everyone except crew member, Basil, votes to continue on. In the coming weeks, the crew struggles to keep the boat operating. Once everything returns to calm, Basil secretly turns them into the police. Franny and Ennis escape. They steal a yacht and continue their journey south.

Throughout their travels, the two companions grow even closer, sharing the truth of their pasts, and encouraging one another. Eventually they reach West Antarctica and discover countless terns. Franny undresses and plunges into the water with Niall's ashes, determined to drown herself and rejoin her husband and daughter. However, while under the water she receives a message from Niall, and decides to resurface and return to her life.