Cara, fresh out of college and grieving her mother's death, finds herself on Martha's Vineyard, unsure of her future. There, she meets Brendan, whose charm and humor captivate her. He reveals a shocking secret: he can breathe underwater, claiming to be a member of the Army Special Forces who has undergone experimental surgery. Cara, enchanted by his devotion and charisma, believes him, and their summer romance deepens. When Cara becomes pregnant, they move into a house Brendan buys, and the birth of their son, Micah, seems to signal a happy ending. However, Cara grapples with Brendan's erratic moods and unexplained absences, attributing them to PTSD from his wartime experiences. She resolves to support him and heal his wounds, but everything changes when Brendan and Micah mysteriously disappear. Five years later, Cara is trying to rebuild her life with another man when a fisherman reports seeing a man and child in Nantucket Sound. This news reignites her hope that Micah may still be alive. As she navigates the blurred lines between delusion and reality, Cara is determined to uncover the truth about her lost love and find her son once and for all.
