On Chesil Beach gives a detailed description of the wedding night of Florence and Edward, in a small hotel on the Dorset coast (Chesil Beach). The story is told in real-time (as in McEwan's Saturday), with two large flashbacks to fill in the background of the two protagonists.
It is 1962, still before the sexual revolution. Brought up in old-fashioned morality, Florence and Edward have so far barely touched each other.
They have very different backgrounds and come to this night with different expectations. She is from a wealthy and intellectual family - her father an industrialist, her mother a lecturer in philosophy at Oxford - , he is from a more sober background (his father is a schoolmaster) with a mentally disturbed mother and the family house run to seed. She is musically gifted and plays semi-professionally first violin in a string quartet, something she wants to continue after her marriage. He is a bit of a floater, rather inconsequential, although he has a certain interest in history.
On the wedding night they have dinner in their room and then quickly retire to the bedroom. Edward is almost too eager to finally sleep with his beloved Florence. He looks greatly forward to this Big Moment. But Florence is awkward and timid and would rather put things off. She feels repulsed by the idea of sexual intimacy, and is also afraid she can't satisfy Edward's rather obvious needs. She has read a terrible medical guidebook, which only makes her feel nauseous.
Of course, between the sheets things go utterly wrong. This is one wedding night that really becomes a life-changing experience! When they later quarrel on the deserted beach, each of them says exactly the wrong things and matters go from bad to worse. Edward doesn't stop Florence when she threatens to leave...
In the last pages we learn that Florence later becomes a famous professional violin player, but remains unmarried. Edwards drifts aimlessly through life, without any steadiness in his relations. He deeply regrets that he didn't show more patience and kindness, there on Chesil beach...