This movie sees Jon Snow (who knows nothing) and apparently only has one facial expression (looking rather sad and worried) being sent from the Roman province of Britannia to the Roman city Pompeii in Italy to fight as a gladiator. For some reason Kit Harington's name is not Jon Snow but Milo and he is not in love with Ygritte but with Cassia [Emily Browning].
It can be seen as a mix between Gladiator , The Horse Whisperer , Volcano  and some really cheesy love movie. Even if the horse whispering and the cheesy love story is somewhat hard to swallow it ain't that bad to begin with - but everything gets a lot worse later. The gladiator scenes are pretty good. Not that violent or bloody but quite entertaining. What really drags this movie down are the endless clichés, the dull predictable story line that includes no surprises whatsoever, and then there's the very unbelievable interaction between Senator Corvus [Kiefer Sutherland] and Cassia.
At some point I actually had the hope that the effects and the gladiator action scenes could save the movie from disaster, but after just one too many stupidity, I was laughing out loud in my cinema seat for the last half hour or so. It started out as a weird mix of genres and ended up as a black comedy pissing all over itself.
The 3D effects are pointless and unimpressive - just go for 2D if you absolutely must see this movie. If nothing else just to have a laugh at it all. I know that Paul W.S. Anderson can do much better than this. I'm not sure if Kit Harington can, but it was not him and it was not the volcano, but the completely lame script and the predictability and clichés that destroyed this movie.