I will try to keep this as spoiler-free as possible, and focus on themes as much as I can, but I'm all over the place here and so proceed with caution...

First of all, I have to say that
Dark Fury is excellent, extraordinarily well-done... it definitely functions as a bridge between
Pitch Black and TCOR, or is intended to...
...but no, it really doesn't explain how Jack goes from being the socialized girl of
Pitch Black to the bitter, antisocial creature of the sequel. At all.
It was delightful to hear Rhiana's voice again, and see a face that actually looks like hers. If only that had been the case in the sequel again... ::sigh::
Anyway, the relationship between Riddick and Jack in
Dark Fury is about what you'd expect based upon their relationship in
Pitch Black. In PB, Jack was a very socialized teen, who worried about and fought for the people around her. In
Dark Fury, that shows up again... she worries about him, she tells him that she won't leave without him even when he refuses to make any sort of statement in return. She struggles hard to keep up with him, and helps him at every turn and opportunity. (Riddick tries to keep her at arm's length and to deny any kind of attachment, but whenever it becomes a real issue, he protects her and worries about her too, and she knows it.)
That sort of behavior is in keeping with the generosity of character that Jack displayed in between bouts of normal adolescent behavior in
Pitch Black, which was why she was such a fascinating character to so many of us. She was a good person who accepted Riddick and liked him, unjudgmentally, without him having to change who he was, and
without her having to change herself, although in typical teen fashion she did try to impress him by putting on tough airs.
Dark Fury Jack is definitely in over her head and on some levels she knows it, but her faith in Riddick to pull them through is absolute, and her determination to help him is as well. And she does. She's not strong enough to keep up all the time, but nothing in Riddick's behavior would leave her embittered because, in spite of his own attempts to pretend he doesn't care about her, he repeatedly
does watch out for her welfare and she knows it and has faith in it.
In the end Imam does express his concern that Jack is in danger of becoming like Riddick, and it may inform Riddick's decision to leave, but there's still nothing in Jack's personality or behavior that would lead her to become embittered. If anything, this Jack would
worry about Riddick, and might conceivably try to find him so she can attempt to protect him... but she wouldn't become unforgiving. Watching the "bridging the gap" extra and hearing a line from TCOR in which Imam talks about Jack never having forgiven Riddick for leaving, I felt myself scoffing.
Dark Fury, in fact, negates that, because this is a Jack who would forgive him without a thought. She might pine, but she would never hate.
Anyway, the Jack in
Dark Fury is definitely believable, and my
god it was wonderful to hear Rhiana's voice again. The storyline is fun, and very cool to watch. Peter Chung and his team have a wondrful visual sensibility.
Toombs is great. Does he look like Wolverine in TCOR, too? Or just in the animation?
About the extras... the "Bridging the Gap" irritated me because Rhiana never appeared in it. It would have been nice to see her live-action face for a few moments, hear a few words from her about what it's like to reprise Jack. (It was very annoying, instead, to have Davalos' face show up. Can't there even be one place where we
don't have to have her foisted on us?)
Animatic to Animation is a lot of fun. You need to watch the full animation first, because this is the bare-bones version of
Dark Fury, with the early bookmark images... the most hilarious part is Vin doing an alternate delivery of his lines where he tries to pretend to be Johns. He raises his voice to a higher range and does a really bad Southern accent, and it's just priceless. Also, some of Rhiana's lines which were slightly drowned out by sound effects are crystal-clear.
I also love the way that Imam has already taken on a fatherly role with Jack in the film, and I wish they'd gone with that approach rather than the Kyra angle. If Jack had been on New Mecca with Imam, well-adjusted and grown up, still the repository of Riddick's soul and humanity, things would have been much more realistic and poignant than having her show up as a bitter, vindictive brat in the prison.
Dark Fury may have been intended to bridge the gap between the first two films, but in a way it only heightens just how badly off-course Twohy then took the universe after that point. The
Dark Fury world still makes sense, and points in the general direction of the TCOR franchise... but somehow Vin and Twohy way overshot their mark and left reality behind.
Listening to Peter Chung in the extras, as he discusses the process of animating and assembling the film, I'm struck by how incredibly intelligent and creative this man is and I suspect I'm going to be buying a lot of his work in the future. I wish, perversely, that
he would be put in charge of directing the rest of the TCOR franchise from here on out.
Buy it buy it buy it. It's what every Jack fan was hoping for... and I'm
very glad I spent my money on it instead of the movie.
Edited: Just got done watching the extras. No Rhiana in them, more's the pity. But I was dreading "Into the Light" because I assumed we'd have more Kyra foisted on us, and amazingly enough she's absent. So aside from a half-second glimpse in "Bridging the Gap," the disk is Kyra-free and her name is
never even spoken. There's a big plus.