On a perfect spring morning, Alexander catches an early train into London, but he never reaches work. Instead, he never reaches work. Instead, he spends the day with Kate, a waitress he has met the previous evening, a woman so unlike anyone he has ever known, she makes the world shimmer with possibility.

Such a perfect day, Nell takes her child Lucy to the seaside, hoping that the sea air will blow away the doubts she has about her life.

As Nell ponders why falling in love is so different from loving someone, Alexander allows himself to imagine leaving his old life behind and starting afresh. And by a strange turn of fate, there's an opportunity to do just that - if he chooses to take it...