You know that the selection of movies at the local theater isn't great when I'm writing about a Vin Diesel movie; he's truly not one of my favorites. He and Nicholas Cage both make me shake my head, wondering what the attraction is for their rabid legions of fans.
That being said, I actually found Riddick much easier to tolerate than many of his others. At least there is no pretense of fine acting; this is a Sci-Fi/Action movie, plain and simple. I have not seen the previous movies in this series, but it was not difficult to follow and it most certainly was never boring. Besides, they gave him a dog, so I automatically softened my opinion just a touch.
Vin Diesel plays Richard Riddick, a character that does have some multi-dimensional qualities. Written as an anti-hero with a past as a convict, he is neither all good nor all bad; I'm not sure I would trust him, but I know I wouldn't want him on the other side. There are no other "name" actors on board, but I found Katee Sackhoff interesting as Dahl, one of the bounty hunters.
There are some great visuals in this movies and the movie zips along at a good pace. I'd go into the plot, but it's really quite basic; Riddick is stranded on a planet with nasty creatures that eat people, other humans come after him, it's not the stuff of great literature. I'd wager that isn't an issue to fans of this series or of Diesel. The box office for the weekend is proof enough of that.
Rated "R" and it is a hard "R"; there is nudity, though no on-screen sex, lots of profanity and tons of violence, way more than my comfort zone appreciates. Certainly not a movie for children or adults who are bothered by blood and there was one scene that really upset me, but I won't go there and "spoil" this for anyone else.