It's 1661 and Louis the XIV is taking over the reign of government from his ministers. D'Artagnan is captain of the Musketeers, Aramis is now a bishop, Porthos is as big, strong and hungry as ever and Raoul, the son of Athos, is still madly in love with Louise De La Valliere. What we do see of Aramis he is plotting and scheming and has a strong interest in a mysterious prisoner in the Bastille.
Louis' effeminate brother Philippe (Monsieur) has just married Henrietta (Madame) of England, but Henrietta only has eyes for Louis, an attraction that Louis returns. In order to allay suspicion of Louis' jealous brother, Louis feigns an attraction to Louise (who is one of Madame's ladies in waiting), but finds himself trapped by his own schemes when he falls in love with her. LOL, some of the antics involved in trying to be alone with Louise that are constantly hampered by Madame's efforts to keep them apart.
This book is different from the preceding novels of the Musketeers -- there is little if any of the swashbuckling, sword fights and derring do that the other books contained. This book focuses on the love story of Louis and Louise, along with the pomp, intrigues and scandals of Louis XIV's court. Although some readers will be disappointed at the virtual absence of the Musketeers in this book, I was fascinated at the glimpses of French history and court life which was beautifully sprinkled with laugh out loud humor reading the antics of the French court, most especially the "revolving" confessions at the Royal Oak tree.
If you've come this far, you've already read The Three Musketeers, Twenty Years After and The Vicomte De Bragelonne. The Vicomte De Bragelonne was originally published in French as one large novel, but is broken into three by English publishers, The Vicomte De Bragelonne, Louise De La Valliere and finally culminating in The Man in the Iron Mask. As other reviewers have noted, this book is more palace intrigue and less of the Musketeers and not everyone will enjoy it as thoroughly as I did, I loved the antics of the French court and had many a good laugh. Dumas is just brilliant (as always) and his dialogue (as always) is among the finest I've ever come across. Highly recommended.