For anyone not up-to-date with this particular franchise, it consists of 2000's pretty good (but not THAT good) Pitch Black and 2004's pretty bad (but not THAT bad) The Chronicles Of Riddick, and if you don't want to be completely lost at the start of this movie, then you'd best do your homework, as Riddick is not an easy entry point. Partly because it doesn't so much as give you a "Previously on…" opening scene, but mostly because it's quite simply a horrendous film.
Riddick is split up into three acts which seem barely connected to each other in any real way; Act One has a bruised and battered Riddick (Vin Diesel) trying to survive on a harsh, inhospitable planet that comes off as I Am Legend In Space thanks to the minimalist dialogue and pairing him up with a puppy. Act Two has mercenaries arrive on the planet to collect the bounty for Riddick's head (literally), and Riddick is almost entirely absent from this section of the movie, and we're left to deal with a large group of interchangeable but all too dislikeable cannon fodder. Act Three is pretty much all of the footage you've seen in the trailer for the movie, and plays like Pitch Black on fast-forward.
Aside from Diesel, the only other constant in this series has been writer/director David Twohy, who filled the 9 year gap between franchise entries with the fun slasher A Perfect Getaway, but has brought none of that enjoyable hokeyness this time around. Everything seems super serious, and between the abysmal script - seriously, some of the dialogue that lead bad guy Jordi Molla (who played pretty much the exact same character in Bad Boys 2) is forced to spit out is truly groan-inducing - and the more often than not shoddy effects, absolutely none of it works. The biggest problem is just how soul-crushingly boring it is, which makes the already-too-long running time feel even longer.
Are there any plus points? Begrudgingly, yes. Diesel is still solid as the lead, some of the OTT violence is pretty fun, and the Karl Urban cameo was a nice distraction. But these are all tiny, tiny needles in a very large, very expensive haystack of crap.