Fans of Warhammer 40000 be rejoicin' last year when news of a Warhammer 40000 film based on the Ultramarines would be released. 40k's a gritty sort of thing, lots of grimdark and deep fluff, so it's hard to turn it into something that translates well onscreen.
I like to think this movie isn't an introduction to the universe, but rather for established fans. It only introduces 2 out of 8 factions and plays out on exactly 1 planet and its orbit. Fans of the universe will most likely enjoy the action and grimdark the movie helps to convey through (flawed) CGI.
Characterisation and portrayals of tech are fully intact, thanks to Dan Abnett as writer. The film stays so true the tabletop game that the characters and equipment were modeled to tabletop specs, to the point where the Land Speeder's weaponry is as comically oversized here as on the tabletop.
Writing and character interactions are solid, conveying the holy duties of the Marines in a way which isn't particularly cheesy. The prayers, warcries and manner of speech stays true to the tone of the fluff, without turning into a hammy mess.
There's plenty of violence and a few thrills along the way, to flesh out the battles. Some people might have expected more action, sooner and others might like less of the grit and violence present; I sit in the middle, there's enough action along the way to the big twist and climax (yes, there is one) to keep viewers satisfied without hampering the story and turning it into a cheap action flick. Ultramarines is a sci-fi thriller at heart.
My only real beef with the film is the CGI, and that seems to be what everyone else is grinding on, too. Facial expressions and facial modeling are far from what I've come to expect in today's CGI films. Everything that wasn't a face was rendered rather well and meshed well with the environment. A few of the bloodier scenes are hampered by the flawed CGI and closeups of characters aren't quite what they could be.
The entire film itself feels like a game of Warhammer 40000 played out in CGI with fleshed out characters. The story of a squad of Space Marines led by 2 veterans who go to secure an ancient relic in the hands of Chaos and must then return it to the ship sounds like something that would be done on the tabletop by a pair of creative gamers.
I'd hand it 7/10, just for keeping true to the universe, good writing, gritty action and flawed CGI. It really does feel like those nerdy toys on your table came to life and started kicking ass.