Alright, here we go...
Retribution picks up exactly where the last one left off, which, after the continuity-breaking introductions of the last two films, is at least one good thing I can say about this film. Alice, Claire, Chris and a bunch of no-name Umbrella prisoners are getting ready to chart a new course for the world on their cargo ship when a brainwashed Jill and a bunch of Umbrella commandos storm the ship, knock out and kidnap Alice and...who knows what happened to the others? The no-names appeared to be either killed or captured, but did this happen to Claire and Chris? We won't find out in this film.
So Alice is taken to an underwater reseach facility in Russia. As Umbrella is known to do, I'm sure. After fumbling around a bit, Wesker (Wait. Isn't he dead? Again, we'll never know how he isn't) reveals over the monitors that he has assigned Ada and another strike group to rescue Alice. And that's basically how the rest of the film goes: Alice and the others need to escape the facility before the facility blows up and drowns them all.
Let's get the good stuff out of the way, because it's a short list. The first time Ada meets Alice is a scene ripped straight from Resi 4. You know, "try using your knife next time". That was a nice touch. Barry Burton is a part of the secondary strike team, and while he looks ten years too young, this is probably the only time bad acting has helped the films. The guy who plays Barry is almost as wooden and awkward as the Barry from the original game. He also has a very "I have THIS!" moment, which was nice-ish.
I believe Retribution also sets a new record for the amount of time it takes Michelle Rodriguez to die. And because of reasons I will explain in white spoiler text later, she dies several times throughout the film. We're taking it to the extreme!!
That's about where the good stuff ends. Retribution is possibly the worst of the series thus far, mostly due to the fact that there is a constant theme of zero payoff.
The action in this is set almost entirely in slow motion, much like Afterlife, and this robs action scenes of their gratuity and excitement. I might have been able to forgive that if the setpieces were decent, but the setups for the fight scenes in this film are hilariously disastrous.
Remember how Alice fought an Executioner Majini in the last film? Well, what's more dangerous than an Executioner Majini? TWO Executioner Majini! What's scarier than a licker? A GIANT licker! What's more terrifying than zombies? Zombies that have guns and look like the ones from Dead Snow! I am baffled at just how unoriginal and small in scale these fights are. And because Alice has lost her super powers, there isn't much to them but constant "blat blat". Tired and lame.
Not much to expect from the acting, but that's par for the course. Milla Jovovich continues her badass yet characterless Alice, Ada sounds the part but doesn't quite look it, Wesker still sounds like a British Agent Smith and the guy playing Leon looks and even sounds closer to Luis Sera, in my opinion. It's his beard, I think.
The big problem is the plot, though. Hooollleeeee crap, some of the nonsense they place in this plot puts the midway point of Apocalypse to shame. In terms of non-spoiler stuff, the facility's realism is an obvious contrivance, but one I could accept if the structure within was clear cut. The facility houses a number of huge testing chambers, resembling New York, Moscow, Toyko and a random suburbia, built for testing the effects of a viral outbreak. It's unclear at the beginning whether it's all holographic or not, and it causes some discrepancies in regards to environmental items (cars, weapons, etc.).
As stated before, we're not going to find out what happened to two of the "major" characters from the last film, and they don't even attempt to explain how Wesker survived. Not a throwaway line, not any fresh scars, nothing. He may as well not have died at all in the last film for all the difference it made here. Same with Luther, the non-descript minor character in Afterlife that just showed up alice and well on the mainland. He's now a part of the strike team. Why? How?
But to discuss the broken plot more, I'll have to dip into spoiler territory. I'll be using tiny text for this section, so skip past it to the next segment of normal text if you wish. If not, highlight it and read on.
Barry's final moments are when he's playing hero, telling Luther and Leon to fall back to the elevator while he holds Umbrella off. They then bring out a captured Ada as collateral, but he heads out, gun in hand, deliberately gets shot, gets one more shot at an Umbrella guard before dying. I was guessing that he was trying to do this to buy Ada a distraction, but she doesn't do anything during this time, meaning Barry commits martyrdom for nothing.
One of the last fights is against a Las Plagas-ed Michelle Rodriguez on a frozen tundra. Alice eventually shoots the ice beneath here feet, she falls in and a ton of zombies...who can now breathe underwater, I guess, close in and kill her. The far shot of around a hundred zombies in the water piling on Rodriguez just looks so incredibly, unforgivably, implausibly silly and, oh yeah, why aren't they going up after Alice? And how can they fucking breathe down there!?
And then we get to the ending. Alice, the freed Jill, Ada, Luis/Leon and this film's Newt make it to the White House, which is being overrun by hordes of various nasties. Wesker...who is now President, I guess, gives Alice back her power...after previously taking it away. He then explains that the White House is the last bastion for humanity, and if they are wiped out there, the race will face extinction at the hands of the Red Queen, Umbrella's sentient AI.
It's unclear how much time passes between each of these films, but we went from Raccoon City being overrun to the T-Virus turning the world into a desert to everything being sorta alright but not really to holy shit, we are the last surviving people on the planet Earth. Inexplicable does not begin to describe it. Also, why does the Red Queen want to destroy all humans? Especially since she is happy using many of them as her army?
Throw in at least two instances of "dead" guys twitching on screen (nothing to do with zombification) and you have a nice fat pile of crap for a film.