The plot of the classic need not be retold here - it was one what we loved in our teen and pre-teen ages about half a century back, along with other classics (of course translated) of Dumas (and his contemporary - of same year of Birth) Hugo, of course along with many others - but these two names strike the mind - the Musketeers (all three of them), Black Tulip, the Hunchback - of recently ravaged Notre Dame, are some of the names I still recall.
This movie is well adapted to the original one, and with Marais in the central role, not much can be improved in acting department. Despite the long duration, about 3 hours - it doesn't bore, of course neither did the huge novels of those times, due to the well paced rendition.
Both the parts had been more or less faithfully adapted from the novel.
Some of the factors are of course missing- for example the method of tunnel digging and disposing off the grits, or the way Dante managed to be inside the sack - but probably they were required for the written version, for the screen version they were not mandatory.
Another major difference - again it didn't matter in the adaptation - was foresaking the Baron Dangler - and rather merging it into two avatars - or mainly into the Caderousse role (Villefort only used the name, for his secret affair) - that would be a missing aspect, especially since instead of the four Marseilles, it was brought down to three, but only for those who have read it. And also probably it reduced some running time - that character and the retribution would have brought in at least another half an hour. And it would have been important - since the side-plot of Morel's daughter and Dangler's son also would have to be retained, to keep Dante's level of revenge in control.
But over all this had been quite faithful adaptation - in two episodes - probably avoiding the third - which would definitely have cause audience exasperation., and without missing much from the main story line, trimming the branches, and characters where it could be. And it didn't much mess up with history either. Of course neither did the novel.
I wonder who was Morel's daughter in (in First part), she was quite pretty, but there is no name in credits or even outside it. She had half the screen time at least, as her father, and may be much more than some other figures - say Emperor Napoleon, King Louise XVIII etc.
Worth watching - if there is still child in you, it won't bore.