During her final semester at a San Diego university, Shannon falls in love with Nate, a graduate student teaching assistant. Before saying goodbye for the summer, the two pledge a lasting love. But there's another woman in Nate's life back in his Boston hometown. Tally is the daughter of his mentor and benefactor, Walter. A year earlier Nate vowed to Walter on his death bed he'd marry his daughter out of gratitude for being a father to him, the son of a single mother. Nate promises Shannon he'll break his engagement. But fate gets in their way, and they drift apart. Never revealing to Nate she was pregnant when they parted, Shannon raises their son Daniel alone, telling him his father was dead. Twenty years later, Shannon and Nate unexpectedly meet again.