Right after they wake the surviving Engineer from stasis there is a bit of an argument about what to ask it. Did David ask Mr. Weyland's question? Elizabeth's? Something else? Is there any way we can know?
Edit: Now we know. In an interview revealed at Total Film with Dr. Anil Biltoo:
The rest of the text of this article stands unedited except for the interview inserts, in italics.
We are forced to reconcile the reaction of the Engineer with:
My supposition still stands and is supported in the rest of the Total Film interview review:
Why wouldn't David say what he had been asked to? He is not concerned with the question or the answer. For him, it is academic at best. He has already made his decision about humanity and given the information he has up to that point, he assumes the Engineers already have their own less than stellar opinion of humanity as well.
My suspicion was he recognized what David was and could extrapolate how long he had been asleep, which may have given him greater motivation to deliver his payload, fearing a galactic outbreak of this violent species. The Engineer did not seem surprised to see us, likely as a diminutive and less impressive form of itself.
I would also have to credit this Engineer with some degree of forethought. He was the only one on this ship to make it back to stasis and secure himself before the pathogen was able to reach him. I suspect he thought it would be safer to be in stasis than dying in the halls.
Here is a recent io9 interview claiming to be the ultimate guide to all Prometheus questions.
What David said to the Engineer is not what set him off. It's not until he touches David's head (in other words, notices that he's an android) that he flies off the handle.
Remember, the whole theme of the movie is the tension between the creator and his creation, whether it is the Engineer and humans, mankind and robots (David), or parents and their children (Weyland and Vickers). While there is truth to David's statement that children can't wait for the death of their parents, at least in the sense that they can then surpass them, superiors tend to want to stay in power. Once the Engineer realizes humans have become creators (gods themselves, just like young Weyland says in the promo video), thus worshiping themselves, he knows he must punish/destroy them, as Zeus did to Prometheus.
In all likelihood, David told him exactly what Weyland asked. He was a pretty smart android and probably knew in advance how the meeting was going to go...
I think David said something like the humans have come here to capture and study you which caught the engineers attention causing it to defend itself. Before David spoke the engineer showed no signs of aggression and also David said don't all humans want to kill their parents (or something along those lines) which showed David knew the humans probably planned on killing the engineer. I think David admired the engineer and decided to warn it of what the humans have came and found it for. The engineers probably never planned on destroying earth and humans in the first place they were unable to go back to earth to see how humans were doing because of the alien outbreak on the ship but the humans assume that the engineers had abandoned them.
protected by Community♦ Jun 16 '12 at 12:36
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