The Riddike movie was actually showing a day early at my local theater. I saw it yesterday, even though it officially comes out today. There were literally 4 people in the theater with my friend and I, it was hilarious.
If you were fans of the first movie, you're probably going to like the third one just as much. It's Riddike doing what he does best - surviving and dealing with pesky mercs.
The premise is fairly simple: Riddike is stranded (yet again) on an inhospitable planet. In an attempt to get back home to Furya, he triggers a merc beacon and attempts to hitch a ride. Needless to say, nothing goes according to plan.
Anyone that saw the second movie will know there was a "unique situation" at the end, and they do explain a bit of what happened there, and why Riddike is on the planet in the first place.
There are also several references to characters and events from the first movie, "Pitch Black" so if you haven't seen it, you may wonder what the hell people are talking about, or why things are the way they are. This movie does do a brief flashblack to explain a few things, but ultimately doesn't hold your hand in terms of the lore - it assumes you've watched the first two films and know who these characters are.
There are some darkly funny moments, especially with Riddike, and plenty of over-the-top gore and mercenaries doing their mercenary thing. If you don't like sci-fi action movies, you probably won't like this one. There's nothing "horror" about this third film at all - it's straight up action. If I can make an anology, this film would be what Alien 2 was to Alien 1.... Lots of mercs, guns, and Riddike in the middle of it all.
The events of the second film, other than a cameo from Karl Urban (who looks nothing like he did in Chronicles of Riddike by the way, haha) are briefly alluded to, but never referenced after. It's almost like they completely ignored all of it, and chose instead to go with a more "Pitch Black" type movie. I think in that regard they succeeded.
A lot of critics are saying the dialogue was bad... I didn't think so. Some of it was kinda "meh" but none of it was particularly bad. Every character felt reasonably authentic - even the ones that weren't fleshed out very long, or had very little screen time.
Anyway - bottom line... if you liked Pitch Black, Chronicles of Riddike, or just watching Vin Diesel be a badass in space - this is a pretty fun movie. Was definitely worth the 7 dollar admission.