I don't know where to start.
First: The plot is nonsensical. There's a colony ship headed to a remote planet to terraform and colonize it. Everyone is in hypersleep, with an android, Walter (portrayed by Sexy Magneto) operating/maintaining the ship. Due to a solar storm or something, the ship is damaged and the crew must wake up. The captain burns to death in his pod before he can be pulled out.
This is where it gets silly. During the repair process, Danny McBride receives a transmission in his spacesuit. After they reel him in they somehow find out that its' coming from an uncharted planet, and this magical spaceship that's low tech except when it has magic Star Trek scanners, determines that this planet is habitable and has vegetation and water and is perfect for human life in complete defiance of the laws of physics without any explanation. Ordinarily I'd let this pass except that the planet they're actually supposed to be heading to can't be scanned this way and some of the dialogue implies that they're looking for it?
So, the new captain decides to visit this planet, over the completely logical objections of his second in command, because he's religious. His unspecified faith motivates him... somehow. It's never explained and he has so little screen time in the movie that his character is never established.
That's part of the problem: This film is so stuffed with plot events that nothing has room to breathe and despite an interminable half-hour or so prologue first act, none of the characters are established. Like all bad movie characters, they can only be described by what they do or wear rather than who they are. There's the smart second in command, the botanist, the pilot who wears a quirky hat, etc. By contrast Prometheus had much clearer character development and actual conflict between the human characters and had something interesting going on, but I digress.
The ship flies to the alien planet where the signal originates.
Now I need to point a something out:
This colonization vessel, which cannot itself land on the planet's surface and is purely orbital, has ONE drop ship that can fly back and forth between the surface and the mothership. For a vessel that's supposed to carry a colony of people on a one-way trip that takes decades I can't emphasize how idiotic and contrived this is. If their ship crashes or breaks down or doesn't work, they're stuck in space with what, parachutes? To make this doubly glaring, several other systems/resources are redundant so there's no justification for this at all.
The take their only ship down to this uncharted and unknown planet which is covered in alien life with absolutely no concern for the possibility of infection, etc. They park their ship and get out, leaving the gate open, and wander around in clothes. Their only protection from the alien environment is fucking hats.
Here's the thing: These people are completely unprepared to explore. They don't have protective gear, mapping equipment, anything. There's nothing they can really accomplish on this planet other than send its location back for something else, and unlike the other Alien franchise movies there's no discussion of a profit motive, i.e. we get paid X for finding this, they do it for... the wonder, I guess, or because they're afraid they might have to take minutes to fix a broken cable a few more times before they get where they're going. (The damage I mentioned earlier amounts to a big wire snapping. That's pretty much it)
The second in command is absolutely right and they shouldn't be doing this. They don't even have the gear!
So of course, two of the crew get infected with something within ten minutes. These are the backburster aliens from the trailers. As in Prometheus, the black mutagen produces these monsters that attack the crew.
This is where it starts getting stupid. A moron on the drop ship accidentally blows up the entire thing by shooting a space propane tank (the cargo hold/docking ramp area of the drop-ship is filled with a bunch of crap that has no reason to be there other than to explode) and strands the crew on the surface. The aliens, which are sensitive to bright lights for some reason, are driven off by David (also by Sexy Magneto, reprising his role from Prometheus) who launches flares for this purpose. How he knows this will work is never explained.
David leads the crew (including Walter, his doppleganger) to an engineer city. I guess this planet is the Engineer homeworld... except they apparently only had one city on the entire planet with a few hundred people.
- The crew splits up. One (female, of course) crew member who isn't even named wanders a good distance from the rest of the crew and sets up in... a bathroom... so she can do her hair?
- David acts oddly, so the crew sends Walter to talk to him. They don't talk about anything important, Walter doesn't ask any relevant questions, and their action consists of a campy homoerotic flute lesson so absurd it made the entire audience break out in laughter in my theater
- Everyone else just sort of wanders around while a couple of crew members try to contact the mothership
-The captain doesn't give any orders and no one listens to him or asks him what to do
- the cast members who aren't doing plot things disappear into the plot dimension when they're not needed to talk or be murdered
In one of the most moronic sequences in the history of film, one of the white photosensitive aliens (which is not the "protomorph", by the way) sneaks up behind the lone woman who's off doing her space makeup for some reason and rapemurders her. This leads to an absurd scene where the captain guy is having a conversation with David, who is trying to communicate with this creature while a woman's severed head floats in a sink behind it.
Instead of letting David tame the alien, the captain man shoots and kills it with two bullets to the chest, which is the only time in the entire movie that guns are in any way effective against the aliens. Subsequently, the captain follows David, who he does not trust and blames for the murder of a member of his crew, down a scary cave and David talks him into sticking his face into an alien egg. The entire scene -which includes David telling him, and I quote directly, "it's perfectly safe", drew a wave of laughter from the audience. If this was supposed to be serious it was a complete failure, and if it's supposed to be funny it's awkward and uncomfortable.
The inevitable happens, and the captain is chestbursted. His last words are not "what happened to me" or "oh this hurts" or "why are you doing this" or anything else; the captain is so solely concerned with faith that he asks what David believes before the alien spawn rips him apart, followed by an (unintentionally, I think) hilarious scene where David plays jazz hands with the cute little alien baby.
While the alien protomorph has enough time to grow to be nine feet tall off screen in about five minutes, David tracks down the protagonist so she can emote about the horror of discovering that David lied to the crew and he murdered Elizabeth Shaw- brutally, and horrifically, using her as a test subject. He also murdered the entire Engineer race and he's the bad guy. He's been experimenting, using the black mutagen to create the alien creatures.
After this revelation, and throwing her around the room a bit (literally) he pins her to a table and forcibly makes out with her.
Blah blah some shit happens, another guy gets exposed to a facehugger, and the mothership sends down some kind of power lifter (which is able to fly... in space...) to rescue the remaining crew. Walter the android dispatches David off screen, there's a tense but completely illlogical and unnecessary battle to kill the protomporh, and everyone goes home.
Then, these idiots get themselves killed through their idiocy: The other guy who was facehugged chestbursts and the alien grows to full size in what has to be less than ten minutes, breaks into the crew quarters, and interrupts shower sex to kill the shower sexees.
Blah blah, they flush it into space.
Turns out, surprise! Walter was killed and replaced by David, who now has a ship full of humans to experiment on with the mutagen.
What I realized after watching this film was this:
There is a rape undertone throughout the movie. David is apparently incapable of sexual congress so he uses the black mutagen to rape people and regards the resulting monsters as his children. There's a distinct sexual undertone to his interactions with his doppleganger Walter and the protagonist Daniels and a very strong imagery of violation with the corpse of Shaw.
What I read in this movie, mostly, is frustration. The whole mess is a reaction to the criticisms of Prometheus. The face hugger scene in particular seems to say: You keep sticking your face in my movies, what do you think you're going to get? The film itself is a screed against creation: It reads as Scott complaining about the act of creating the movie Alien. He's been defined by it, and now that he's not giving the audience exactly what they want he's a villain. His creation has mutated and become toxic.
The humans/David act as proxies for critics and the audience. The Engineers are Scott himself- pure artists concerned with form who are destroyed by someone stealing and perverting their creation.
What offends me most about this film is that it takes all the intriguing possibilities of Prometheus and shits all over them. The backstory behind the aliens isn't interesting or mysterious. The engineers are not godlike and unknowable. The xenomorphs were created by a robot who hates humans because the guy who made him was a dick, which justifies him being a psychopath and savagely torturing and experimenting on a woman who was kind and respectful towards him.
As I always say, the existence of this movie does't diminish Alien. It's still a great film. This one, however, is bad, and superfluous, and angry. Not since The Dark Knight Rises have I seen a film that gets off on subtly insulting the audience for watching it so hard.
It's a weird film. I actually liked watching it. It's beautiful. The art design is gorgeous, it's amazingly well filmed, the special effects are incredible, but they can't save an aggressively terrible script. Now that I've seen it I have no desire ever to watch it again because it has no redeeming value outside some spectacle.
Oh, and I have to mention:
These space colonists are armed with AR-15s. This movie takes place something like a hundred years from now, meaning that these people are equipped with 160 year old rifles. That would be like sending astronauts to the Moon with flintlock muskets. These things bother me.
Alien: Covenant isn't a science fiction movie, at all. It doesn't deal with the impact of scientific advancement or discovery on human society, culture, or life. It's an amazingly pretentious slasher movie set in outer space... lazy outer space that's exactly like Earth.