Exactly how steamy is this story?
PG-13
There's not really any sex that happens in The Ambassadors. Not on stage, anyway. But there's enough hinting toward it for this book to deserve a PG 13 rating. For most of the story, Strether is convinced that the relationship between Chad and Madame de Vionnet isn't sexual. But when he sees the two of them sneaking into a countryside hotel, he realizes that the two of them are definitely going there for some steamy, adulterous sex.
Again, you'd hardly know this because James' language is so polite and Strether's mind is so not-dirty. But hey, sex is sex, and whether Strether tries to ignore it or not, it's there.