I didn't end up watching this at the cinema but picked it up the other day. Anyway, having watched it, I have to say, I was not impressed.
We start off with a scene of a planet upon which one of the "engineers" appears to commit some form of sacrificial rite that involves the ingestion of some black goo (more later) that causes him to rapidly break down and imbue the water with his own genetic material. We see subsequent scenes of cellular division giving the impression that he's seeded this unknown planet with his DNA in what is later alluded to as the process by which humans were "engineered" by his race.
I say unknown planet, because it's seemingly not Earth. If it is, then he's seeding it at a point geologically close to the present and the terrestrial life with which we share the bulk of our genetic makeup is already abundant, regardless of how barren the waterfall area appears. I say this as he's surrounded by geologically old terrain and able to breathe quite freely (mosses and lichens are visible in the opening scene too). And as we discover later, he's genetically identical to modern humans, so a terrestrial atmosphere is definitely impled. Note he's supposedly genetically identical, despite the fact he clearly has various known genetically-regulated differences, such as an apparent lack of melanin, superior height, physique and strength (and ability to tolerate higher carbon dioxide levels) than your average modern human. The real issue of course, being the strangely coincident baseline genetic compatibility with existing life on the planet. Perhaps his race was also present billions of years before and seeded the initial life too, in which case, his actions might be a sort of genetic update for the existing biota.
Anyway, my real beef is with the rest of the plot. Two "scientists" (we aren't told their field, their specialisations appear to vary through the movie from archeologist/anthropologist to geneticist) conjecture that the similarity of a set of ancient depictions of giants pointing at what they assume is a constellation indicates the existence of an alien race that "engineered" mankind and moreover an invitation to come and visit one day.
On this unsound premise, big-question-pondering, one-foot-in-the-grave industrialist owner/foumder of Weyland corp is persuaded to fund a multi-trillion credit venture to an "extremely distant" star system (3.2x10^14 km according to the info in shot - which is actually only ~34.6 light years) that matches the configuration of the stars depicted in said ancient renderings. Constellations that over the ~30,000 year period from the oldest cave painting to the most recent example could have changed, but we'll let them off for not realising that.
Their ship arrives after 2 and a bit years of travel (which, assuming a local timeframe reference requires they have travelled some ~16x lightspeed to do so) and the crew are woken from suspended animation. It turns out that they are joined by some additional mission specialist "scientists" in other disciplines to help them analyse whatever they find, an android, company rep and some security guys. I say "scientists" because not one of the useless buggers behaves scientifically at any point.
They watch brief recorded intro by the self-declared "long dead by now" Weyland, in which he introduces the reason for their mission to a crew that by and large seemed unaware. Long dead? I guess it's possible but as they travelled 36 light years in just over 2 years, all that time-dilation centuries passing on Earth while they are gone went out the window. Also, you'd not send out a scientific expedition on a journey that would take many centuries to return, we just can't plan that long term, bless us. As to why most of the crew had no idea what they were signing up to, I can only assume extremely large wads of cash were used as incentives.
Dr's Shaw and Holloway present their theory to a sceptical crew. Rightfully, Dr Shaw is challenged if she has any evidence to back up her theory, where she replies with "I don't, but it's what I choose to believe.". As any good scientist surely would...
Upon arrival at this strange new world, no time is spent surveying and mapping the globe to look for any signs of present or previous habitation, resources or even a safe landing area. Instead, they plunge headforth into the earth-like but with toxic levels of CO2 atmosphere, through storms and over vast mountains and look around for a landing site. And as if by magic, they chance find a valley with a series of pyramids, encircled by walls that protect them from the (as we soon discover, quite ferocious) elements.
Despite there only being 6 hours of daylight left, instead of doing whatever mundane "hey, we just touched down on another planet" checklist, securing their landing site and getting a decent night's kip before a hard day of Science! on the morrow, our erstwhile Dr's insist in rushing headlong to the nearest structure and venture inside, cuz it's like, you know Christmas and all that. Also, I imagine that in 2093, the idea of sending a suitably sterilized, unmanned probe into an unknown, potentially hazardous alient environment to do a man's job is just fronwed upon.
Once inside, the "geologist" sends a couple of drone devices around that map the structure in high resolution 3D so that, you know, they won't get lost or anything.
Further inside, Dr Holloway discovers the atmosphere relative to outside is depleted in CO2 and thus, obviously, entirely safe to breathe. So, he does what any good scientist would do and removes his helmet. Never mind that the reading could be wrong, or not include information on unknown chemical or biological agents that might be present, or heaven forfend that he might contaminate the site with his own crap. And after a couple of seconds, his colleagues all follow his lead.
Not long after, they discover a supposedly ~2000 year old decapitated corpse of one of the (humanoid) aliens. At which point, the geologist bloke, gets the willies and decides to head home to the ship, unnacustom as he is to long dead things, such as fossils, for example. The biologist, goes with him as you would expect. After all, it's not as if encountering the remains of a humanoid alien would be the sort of thing to get his scientific curiosity piqued. The two leave together, and despite the fact it was the geologist that released the mapping drones, proceed to get completely lost within the structure.
The remaining group enter a room by way of door that decapitated said alien and find his head. The room has a large humanoid head sculpture and various vase like objects. While appreciating the room and it's art, Dr Shaw notices that the renderings start to change as a likely consequence of altering the atmosphere. No sh*t sherlock? Perhaps you should have kept your helmets on instead of breathing all over everything.
There's way more to post, but I'll continue my diatribe later...
