I used to be a film critic for the college newpaper, and I watched hundreds of movies over my 5 years working for them.
This movie, in 3d, was an
11 out of 10.
Hands down, it was the most amazing movie, visually, I've ever seen. If you see it on a flat screen, I imagine it would be sort of vanilla.
With a script by world-fantasy-award winner Neil Gaiman, and acting by Anthony Hopkins, Angelina Jolie, and a stellar performance from Brendon Gleeson, it is, without a doubt, the most entertaining and engaging incarnation of this particular story in history.
And I've read at least 5 versions and seen other visual representations, including the related "13th Warrior."
The wife, who is NOT a movie buff, also felt the same way, saying the characters, effects, and in particular the 3D design of the film simply blew her away.
In the literature, there was never a reason for Grendel's fury or Hrothgar's surviving the night... it was always just a given. Gaiman takes all the classic elements and weaves a coherent modern story, just as he did for Snow White in "Snow, Glass, Apples."
See it. And see it in 3D, even if you have to drive an extra 30 minutes to do so.