Shark Heart: A Love Story is a 2023 fabulist novel by Emily Habeck that follows the short-lived marriage of Wren, a type-A personality with an unspecified job in finance, and Lewis, a high-school theater teacher who is diagnosed with an incurable mutating condition that transforms him into a great white shark. Shark Heart is Habeck’s debut novel and received widespread critical and popular attention for its innovative approach to Navigating Terminal Illness and Anticipatory Grief and loss. The work also explores themes of Transient but Formative Female Relationships and Life as Metatheater.

This guide refers to the 2023 Kindle e-book edition of the text, published by Marysue Rucci Books.

Content Warning: Shark Heart contains detailed discussions of terminal illness, suicidal ideation, domestic abuse, alcoholism, and grief, as well as elements of body horror.

Plot Summary

Wren and Lewis meet in a cafe in 2012 while Lewis is on a date with another woman. The date is going poorly, and after it ends, Lewis asks for Wren’s phone number. Lewis is a romantically minded theater teacher who has moved back home to Texas after failing to launch an acting career in New York City. Wren is a pragmatist who works in finance and has also returned to her childhood home of the Great Plains. Though they have conflicting personalities, their relationship becomes increasingly serious.

The couple gets married, but shortly after the wedding, Lewis begins to notice that his body is changing in strange ways. Wren encourages him to go to the doctor, and he is soon diagnosed with a “mutation” that will transform him into a great white shark within a year. As his condition progresses, Wren and Lewis cope differently. Lewis decides to finally complete a lifelong goal of writing a play, and he bases it on his disease and marriage with Wren. Wren becomes an avid swimmer, befriends a woman who is pregnant with twins who have mutated in the womb, and begins to form a plan to live on a boat in the ocean alongside Lewis once he has completed the transformation. Toward the end of his illness, Lewis starts to become violent, and the doctors determine that it is time for him to be released into the ocean. Wren drives him to California and releases him at the beach. She tries to carry out her plan, but Lewis tells her that it is impossible for them to be together, and they part ways permanently.

In Part 2, the story moves backward in time to meet Wren’s mother, Angela, during the summer of her 15th birthday. At home, an absent father and a mother with an alcohol addiction drive Angela to stay out of the house as much as possible; she goes to her local country club’s tennis courts regularly to distract herself. There, she meets Marcos, an older boy (his age is never specified) to whom she is immediately attracted. Marcos and Angela become romantically attached, and soon Angela becomes pregnant. Though Angela is initially happy about these developments, Marcos quickly begins to engage in abusive behavior, physically harming Angela and restricting her access to friends, school, and work.

To survive, Angela begins working at a local motel, where she meets her coworker Julia, a Chickasaw woman who shows her kindness. Julia and Angela form a friendship that keeps Angela safe, as the Chickasaw community welcomes Angela into their homes, provides her with food, and monitors the physical threat that Marcos poses to her. After a particularly violent outburst by Marcos fractures Angela’s arm, the couple separates, and Angela leaves to live with Julia’s family. During this time, Angela begins to kindle a romantic relationship with Julia’s brother, George, which effectively disintegrates her friendship with Julia. As Wren begins to grow up, with George serving as a father figure for her, Angela is diagnosed with a mutation that will eventually transform her into a Komodo dragon. Angela ends her relationship with George at this juncture, and Wren is forced to mature quickly and become her mother’s caretaker. By the time Wren is 24, Angela has completed her metamorphosis.

Part 3 returns to Lewis, who is living as a great white shark in the Pacific Ocean. Lewis undergoes an intense mental health crisis after leaving Wren. Struggling to adjust to his new life as a solitary animal in the ocean, he tries repeatedly to starve himself to death, but his animal instincts prevent him from doing so. At his lowest point, he meets Margaret C. Finnegan, another former human who has been transformed into a great white. Margaret and Lewis have conflicting personalities, but Lewis begrudgingly accepts her companionship because he needs her help learning how to hunt and because he is tired of feeling so lonely. By the end of Part 3, Margaret has helped Lewis process his grief over Wren and develop his new identity as a shark.

In the book’s Epilogue, Wren discovers that she is pregnant with Lewis’s baby. She names their baby Joy. Through motherhood, she is able to reconnect with both Lewis and Angela.