Oblivion is shite. The reveal that the alien was an AI followed by the movie ending sucked balls. Who built the fucking AI? Where are they now? I want answers! I watch/read science fiction for the ideas, and there was precious little of it here. Also, plot holes galore.
1) If the alien HAL (yes the whole thing was like an inferior homage to 2001: A Space Odyssey) was unable to completely excise memories from the brains of its clones, how could it have made an army of them exterminate humans on earth? One would have thought that, at some point, at least some of them would have wondered what they were doing killing, like, all the humans. If it was able to completely excise memories, why did it leave memories of Olga intact in the technicians?
2) Given that HAL was capable of creating an army of human clones that were willing to wipe out humanity, what was the fucking point of hiding the existence of other techs from the techs and weaving a convoluted story about migrating to Titan? This just makes it a) possible for them to accidentally chance upon each other and realize that some huge con was going on, and b) isolated and unable to help each other when shit hit the fan.
3) Once Tom Cruise was no longer part of an "effective team", why would his bubble jet thingy still work? One would imagine a superior alien AI would have been capable of building machines with some sort of override mechanism. Even I, an inferior human intelligence, am capable of thinking up the devious ploy of letting Tom get on the plane with Olga, then disabling the manual controls and bringing them to the Tet by remote control (even if it were too far away to control it directly, why could a drone not have done it?), thereby rendering the whole chase scene unnecessary.
4) How the flying fuck could it have been possible for Tom to outmaneuver the drones anyway? They are machines. They are capable of nanosecond reactions and pulling Gs no human could possibly tolerate. WTF?
5) The "scavs" are well-organised enough to put out sentries. We've seen this. We've even seen the sentries destroying a drone. So why, after the Second Coming of Cruise to the base, was there no advance warning of the drone attack that wiped out, like, 90% of all the scavs? Especially bearing in mind that the arrival of Cruise could only mean that he had defected and the probability of retaliation had significantly increased? Were all the sentries going like, aww man, let me see his purty face! And did Morgan Freeman just go like, ah what the hell, I'm sure the drones won't attack us now that one of the Tom clones, the only humans familiar with alien HAL technology and who thus poses a greater threat than all the rest of us combined, has defected? Seriously, put out more sentries, man. And set some booby traps or something. Mind-boggling incompetence. It's a wonder they weren't wiped out sooner.
6) One would imagine a superior AI would have taken the precaution of screening the bubble jet thoroughly for, oh, I don't know, enough weapons-grade radioactive material to completely obliterate a giant spacecraft before letting it enter the ship. Also, why not tell Tom to open the coffin thingy immediately after entry to ensure that no Morgan Freemans were brought into its presence?
7) For that matter, why bring the defective clone into its presence at all? It's not like there was a shortage of Tom clones. Command the Tom clone to release the coffin and then kill him. Since he said that he has brought Olga on board to ensure the survival of her and the human race, he should be OK with that. Why not take him at his word and blast him? If he was unwilling, just blast them both to be on the safe side.
8) Why were the clones necessary at all if HAL only desired water? Just nuke the shit out of humanity, then take the fucking water from a sterile planet.
9) Why come to earth at all? Just harvest the water from asteroids incapable of fighting back.
10) Why bother with water at all? Just orbit the sun for a while and soak up all the solar power it needs.
I have no idea how anyone could possibly have enjoyed a movie with so many glaring inconsistencies. Oh, and there are spoilers so that you don't have to sit through it.