On a train to Rome, Samuel Perlman introduces himself to a striking, much younger woman deep in thought named Miranda. He tells her that he’s on his way to Rome to visit his son but is worried about imposing on him. He describes how he and his son take long walks around Rome together, visiting sites of personal significance in a kind of pilgrimage. Miranda tells him about her own father, who needs constant care but whom she loves. Samuel worries that a lost and intense love from his past has made him either averse to serious love again or constantly in love—Samuel can’t tell which. They discuss the fleeting nature of passion, how difficult it is to stay in love with someone once the mystery of getting to know them is over. Samuel reveals that he is divorced, but that the woman he loved the most, Miss Margutta, was not his wife. Miranda reveals that she has a difficult time in relationships because she soon tires of a man’s ways and need for her.

Samuel and Miranda discuss the value of their therapists. Samuel likes to talk to his therapist about missed opportunities, all the chances he didn’t take in life.