We have Newland Archer and May, very rich, very conservative ( I found it hard to imagine Americans being this!), very set in their ways and oh so rigid in what is right, correct and wrong. The family is described as being tribal and will close ranks against outsiders who dare to think they could infiltrate into what is a very closed society. Outsiders will remain outsiders till the end of the book when we see a disintegration of this exclusivity and the freedom of society for which most of us view America as being.
Archer and May are people from their own society - hidebound by rules though Archer does hope to break away from the rigid outlines set out by society. May is determined to carry on just the same as her predecessors. To this we add the third side of the triangle - Ellen - broken away - married a foreigner, albeit a Count and now back in a kind of disgrace as she has dared to even think of divorce. The disgrace is to the clan - not merely Ellen - and here the whole family aligns itself together with the exception of Archer who understands why Ellen is seeking a divorce. To the rest of the family, irrespective of why and how and the validity of the reasons is the fact that a married woman's place is by her husband irrespective of whatever the husband will or will not do.
The story deals with how society and family moulds an individual and how we all tend to stay within these barriers (more or less). Maybe we break out more today than in the 1870's but in Newland Archer's day the family and society were the make or break in your life and you jolly well followed society's rules if you knew what was good for you. How Newland and May stay together, how Ellen goes back to Paris and how life continues in the same mould as before is the story of the book.
A happy ending for Newland and May's son - a twist in the tale almost but you must read the book to know that. A classic this one!