I don't know about 3 and 4, but #5 isn't at all a Three Musketeers book.
I believe you are mistaken. Actually, and I didn't know this myself until I started reading these novels, and the Oxford translations have all kinds of notes, references, and history about the novels.
I read the Three Musketeers which was great, and then Twenty Years After because my father said, "Hey you know there is a sequel ?" Then read the notes for Twenty Years After, and thankfully I did because I was set to read the Man in the Iron Mask, but after I found out there were two to other books before it, I stopped and read the two books before it.
Books 3, 4, & 5, in the original French version, are one huge book ( The Vicomte of Bragelonne: Ten Years Later). When the english translated the series, they separated the final book into three parts (The Vicomte de Bragelonne", "Louise de la Vallière", and "The Man in the Iron Mask).
But, you don't have to take my word for it. A little research will show it to be true.
Info on the Three Musketeers
http://en.wikipedia.org/wiki/The_Three_Musketeers
The Three Musketeers (French: Les Trois Mousquetaires) is a novel by Alexandre Dumas, père, first serialized in March–July 1844. Set in the 17th century, it recounts the adventures of a young man named d'Artagnan after he leaves home to become a guard of the musketeers. D'Artagnan is not one of the musketeers of the title; those are his friends Athos, Porthos, and Aramis, inseparable friends who live by the motto "all for one, one for all" ("tous pour un, un pour tous").[1]
The story of d'Artagnan is continued in Twenty Years After and The Vicomte of Bragelonne: Ten Years Later. Those three novels by Dumas are together known as the d'Artagnan Romances.
The Vicomte of Bragelonne: Ten Years Later ["The Vicomte de Bragelonne", "Louise de la Vallière", and "The Man in the Iron Mask." ]
http://en.wikipedia.org/wiki/The_Vicomte_of_Bragelonne:_Ten_Years_Later
The Vicomte of Bragelonne: Ten Years Later (French: Le Vicomte de Bragelonne ou Dix ans plus ****) is a novel by Alexandre Dumas, père. It is the third and last of the d'Artagnan Romances, following The Three Musketeers and Twenty Years After. It appeared first in serial form between 1847 and 1850. In the English translations the 268 chapters of this large volume are usually subdivided into three, but sometimes four or even five individual books. In three-volume English editions, the three volumes are titled "The Vicomte de Bragelonne", "Louise de la Vallière", and "The Man in the Iron Mask." Each of these volumes is roughly the length of the original The Three Musketeers. In four-volume editions, the names of the volumes are kept, except that "Louise de la Vallière" and "The Man in the Iron Mask" are pushed down from second and third to third and fourth, with "Ten Years Later" becoming the second volume. There are usually no volume-specific names in five-volume editions. French academic Jean-Yves Tadié has argued that the beginning of King Louis XIV's personal rule is the novel's real subject.[1]
What throws most people off is that only d'Artagnan is still called, d'Artagnan by the time the Man in the Iron Mask roles around in the series. The Three Musketeers are all the same people (thus explained how this happens in Twenty Years After, The Vicomte de Bragelonne, Louise de la Vallière) but there "titles" have changed because of their rank.
Athos = Comte de la Fère
Porthos = Baron du Vallon de Bracieux de Pierrefonds
Aramis = René d'Herblay, and then rises to the rank of Bishop René d'Aramis de Vannes.
Can't just watch the hack of a movie called the Man in the Iron Mask. Cause it does the series and the acutal novel absolutely no justice.
I cannot believe I am debating with Stout about literature. Who says football fans are not deep