Sean [Cameron Bright] and Anna [Nicole Kidman] are a married couple living in New York City. Sean is heard lecturing to an unseen audience, explaining that he does not believe in reincarnation. After the talk, he goes for a jog, collapses, and dies, setting a quiet, unsettling gravity over the years to come.
Ten years pass, and Anna accepts a marriage proposal from her new fiancé, Joseph. When Clifford, Sean’s brother, arrives at Anna’s engagement party, his wife Clara excuses herself, saying she forgot to wrap a gift. Instead, she buys a replacement while a young boy secretly watches, an eerie hint of the strange path ahead.
Sometime later, at a party for Anna’s mother, the boy sneaks into the apartment and claims to be Sean. At first, Anna dismisses the claim, but a letter from him the next day convinces her that the boy truly believes he is her reincarnated husband. That night, Anna and Joseph discuss the note, and when the building watchman seems to know the boy’s name is Sean, Joseph goes downstairs to investigate. Sean refuses to recant, and Anna witnesses him collapse into his father’s arms.
A message is left on Anna’s answering machine by Sean, which her mother overhears. The next day, Anna’s mother mentions that Sean wants to meet in the park—and that she will know the exact spot. Anna rushes to Central Park and discovers Sean waiting at the very place where her husband died. He offers to submit to questioning.
Anna’s brother-in-law Bob, who is a doctor, records Sean’s responses, and Sean answers every question, including intimate details of Anna and Sean’s life together. Sean is brought to Anna’s by his mother, and he can identify the connections between the dead man and various parts of the apartment. Everyone else remains doubtful, though Anna clings to the possibility. The mood thickens as Anna’s sister Laura treats Sean with contempt, and the family grows increasingly anxious.
When Anna misses an appointment with her fiancé to spend time with Sean, Joseph’s concern—not only about the boy but about Anna’s odd behavior—deepens, and his jealousy comes to a head when he physically attacks Sean. Sean runs away, and Anna follows, culminating in a kiss between the two.
Anna’s belief in the boy’s story leads Clara and Clifford to meet him. Clara encounters Sean at the door and reveals that she and the dead man were lovers. She asks the boy to visit her later. When Sean visits Clara, his backpack is stuffed with Anna’s love letters to Sean. The letters—meant to be Clara’s spiteful engagement gift—had been secretly unearthed by the boy on the night of the party. The dead man had given Anna’s letters to her unopened as proof of his love. Clara points out that if he truly were a reincarnation, he would have come to her first, and Sean, overwhelmed, runs out, unsettled by the implication that to be Sean he would have to love Clara too.
The turning point comes when Anna finds Sean. She suggests that they run away and marry once he is of legal age. He tells her that he is not the dead man, and, with that bitter truth looming, Anna apologizes to Joseph, and the two are married near a beach. After the ceremony, Anna wades into the ocean’s edge in her sorrow, while Joseph finds her and offers quiet consolation, his whispered reassurance guiding them back to shore as the sea keeps its ancient, inscrutable rhythm.
