I am a bit amazed that this film has been critized so much, and this is why I am reviewed it only now, after having bought it over six months ago, seen it twice, and thoroughly enjoyed enjoyed it each time.
As another recent has noted (Vandal), I also like it both despite of and because of the main criticism levelled against it: that it is disjointed, with, allegedly, too much crammed into one film. Stating that the film includes bits and pieces from three of Perez-Reverte's books on Captain Alatriste is quite correct. However, this did not "ruin any dramatic potential" for me. Quite the opposite in fact, it added some. Rather than a continuous, linear and somewhat conventional story of Captain Alatriste over some 20 years (from 1622 to the battle of Rocroi in 1643), you get glimpses, the main episodes in the life of a profesional and veteran Tercio. Whether this is deliberatly intended or whether it is just the result of wanting to include as much of the three books as possible is rather irrelevant to me. This is because I found the end result rather good and, unlike others perhaps, I do not necessarily need my films to spell everything out.
Interestingly, I also felt that, by concentrating on the issue above, most reviewers seem to have missed what for me was the main point of the whole film: the hero's (or should I have written the "anti-hero"?) rise and fall, which mirrors that of Spain. Two other reviewers have captured parts - but only parts - of this core theme that makes the film come together.
One is Charles Vasey in ghis "Golden Century" review. This is indeed a film about the Spanish wars in Flanders against the heretics and rebels that would become the Dutch: heretics because they were Protestants, and rebels because they rejected the King of Spain's authority and were fighting for independence which they would finally obtain, becoming the United Provinces (the current Netherlands). These endless wars lasted the best part of 80 years and were quite horrific, even for the time, as the film shows rather well with its episode on canal warfare and the other episode on the siege of Breda. Spain, who would finally be defeated a good 20 years after Rocroi (in 1643), would also be bankcrupted and bled dry by the endless war, while the Dutch received support from England, and even sometimes from Catholic France, both bitter rivals of Spain. This is largely seen in the film.
The other reviewer (Bob Salter) rather insisted on Alatriste as a "killer for a few coins". This is the other part of the story, that of an increasingly impoverished - or at least unequal Spain where demobilized soldiers were no longer paid and had to hire out their swords to anyone willing to pay them the few coins that would precent them from starving, while the great nobles intrigued, plotted and got ever richer. The film's contrast between the arrogant and despising attitude of Olivares (very well portrayed, by the way) and the impoverished but still proud Alatriste is one of the most powerful scenes. Reduced to misery, Alatriste, and all of the other demobilized soldiers who only have their swords to live on, are simply ready to accept ANY job to survive, especially killing somebody.
One the object lessons of the film is to show how the most valiant and brave of Spain's sons, those that bled and died on its numerous battlefields, were the most poorly and dishonorably treated, as if they were beggars, when they went home and were no longer fighting a war. So, it is hardly surprising if some reviewers found the film gloomy: it's all about misery, doom and gloom, on the one hand, and heroïsm and honor (but NOT glory) on the other. The first piece occurrs whenever Alatriste is demobilized (and therefore not paid anything anymore by the Crown). The second, when he is fighting for the Greater glory and benefit of his (somewhat unworthy) King. These contrasts are, of course, quite deliberate in the film, and also exist in the books. This is, after all, the Spanish and modern version of the Three Musketeers: it's realistic and feels very real. It's about doom, gloom and honour, and don't expect any "Hollywodian happy ending". There are a couple of love stories, of course, but they do not end particularly well and the couples do not exactly end up by ridding of into the sunset!
Finally, there is, of course, the costums, which are wonderfully accurate to the extent that they seem to be straight out of a museum (the Prado, of course!), the actors' performances, on which so much has already been said that I do not feel the need to add more comments (I loved Vigo Mortensen's performance, but I also liked many of the others, starting with the actor playing Olivares) and the battles and duels, which are filmed in such a way as to make them as gripping and as realistic as possible. The last scenes - those of the battle of Rocroi - are particularly good, and perfectly historical by the way: the Tercios did not surrender and fought to the last before being overrun by the French cavalry. The film's end, which does stop abruptly, is certainly deliberate: either there was nothing more to show, apart from the final slaughter, or this was allowing for a Part 2 sometime in the future. After all, the film only uses Perez-Reverte's first three books on Alatriste, so there is still room for at least one sequel...
Anyway, in case you had not realized yet, I loved that film and it worked fine for me...