It's hard to know where to start in describing the depths plumbed by Beowulf. <warning this rant will contain spoilers - mainly on the basis that crap can't be spoiled any further than it already is> I acknowledge that books (or poems in this case) & the derivative film should not be identical but the film should at least follow the basic plot and not throw it out of the window. In that case they should have renamed the film like the 13th Warrior which, issue of costume aside, was an excellent adaptation of the Beowulf story. The main criticism has to be how horribly they have distorted the story by making Grendel's mother some kind of monstrous seductress, who ensnares both Hroðgar and Beowulf. This completely negates Beowulf's role as the peerless hero of the tale, who not only behaves honourably and faithfully, representing in turn the virtues of the king's thegn and then later the king himself. He is the Anglo-Saxon paradigm of how nobility & royalty ought to act. I cannot understand why the script writers/director (Neil Gaiman, at least, really ought to have known better) felt the need to make such a fundamental change to the script. In addition the dragon in the poem is entirely unrelated to the Grendel/Grendel's mother episode (best described as a feud between Hroðgar & Grendel - again note Grendel's mother only kills Æschere, Hroðgar's most trusted retainer in revenge for the death of her son - thereby adhering to the rules of the feud: the retalation most be proportionate to the original need for vengeance. As <yet another> side note the author of Beowulf is at pains to point out that part of the monstrosity of Grendel lies in the fact that he will not accept compensation or any peacemaking overtures. The same is true of his mother - something, which to some degree, the film ignores). Another major problem was the treatment of Christianity in the film. While the poem makes clear allusions to Christianity it is also explicit that it is describing a pagan world. The film sets itself in AD 507 (not an unreasonable date), some two to three hundred years before Christianity began making inroads into the Baltic/Scandinavian world in which Beowulf was set. As such it was utterly unnecessary and as glaring an anachronism as the architecture used in the film - no building in stone in the Germanic world in the early sixth century. Furthermore it also serves to negate some of the central themes of the poem, notably the inevitable and destructive nature of feuding in a pagan context (Christian forgiveness and the primacy of sacrally anointed kings who removed the individual's right for vengeance reduced although did not remove the occurrence of feuding) and the manner in which society's hierarchy and modes of behaviour were maintained by honour codes rather than moral/Christian imperatives. Perversely the loose sexual mores of the film which are employed, in part I suspect, to represent the pagan nature of society are entirely out of place. Germanic society was prudish with an acutely developed sense of status and honour - openly committing adultery against a woman was a slight to her honour and that of her kin (see Tacitus) - with shame playing a powerful role as a social control. The only exception might be the treatment of slave women but even here discretion was advisable. In the poem there is no suggestion that Wealhþeow is anything other than a loyal and loving wife to Hrothgar. Finally in the list of major problems relating to the story there is the frankly bizarre treatment of two major characters in the story: Unferð and Wiglaf. The former (his name means Unpeace or strife in OE) is an important character as providing a contrast to Beowulf in how a King's retainer ought to behave. Wiglaf is placed in juxtaposition to Unferð. He only appears as a young man in the poem when Beowulf, as the by now aged king of the Geats (note not the Danes, where Hroðgar & Wealhþeow's eldest son, Hreðic suceeded to the throne only to be subsequently killed by the Heathobards), fights the dragon. The dragon, enraged by the theft of a gold cup from its hoard by a slave, is fought by Beowulf who takes twelve warriors with him (the final fatal encounter with the dragon can be seen as a metaphor for the evils of greed and pride - especially that Beowulf eschews the use of more warriors and leads the attack against the dragon as being an indicator of prideful behaviour contrasting with his earlier modest life) who then abandon him with the exception of Wiglaf. Wiglaf, therefore, stands in direct contrast to Unferð showing himself to be a true, loyal and brave retainer worthy of Beowulf's patronage/lordship. The two together slay the dragon by using sword (Beowulf's fails him) and knives. A less major irritant was the incident with Finn. In the poem Finn was long dead by the time of Beowulf; he is mentioned in a poem within the poem as an exemplar of how diplomatic royal marriages can go wrong and how feuds can destroy even the most powerful kingdoms. The fight at Finnsburgh takes place perhaps 60 - 80 years before the setting of the main events in Beowulf. Equally irriatating is the fact that in the poem it is the Geats under King Hygelac, Beowulf's lord, who attack the Finns and are bloodily repulsed with Hygelac losing his life. There were plenty more annoyances re how badly the film represented the poem but I've probably bored you all enough. I would also note that the CGI is moderate at best, almost entirely removing emotion from the faces of the main characters and with one or two exceptions the voice acting is poor. Beowulf fighting naked is laughable and reduces an heroic scene to that of schoolboy fnar, fnar prurience (as a final note it's worth mentioning that he fights Grendel's mother wearing armour and it is his mail that saves him from the water demon's attacks). Also they bastardized the Old English spoken by Grendel into a form which was neither one thing nor the other. An altogether dreadful film and up there with U-571 as another example of Hollywood of butchering a perfectly good story. Avoid at all costs.