Question: What happened to Ogilvy?
Answer: Ray couldn't trust Ogilvy to be quiet when the aliens arrived. So Ray had to kill Oglivy in order to save him and his daughter.
Question: Before Tom Cruise is ushered into the tunnel in Boston, he tells the army man, "______ is the key." What does he say; what is the key?
Answer: It is actually the army guy who says this, not Tom Cruise. Cruise notices the birds are able to land on the tripod and realizes the shields are down. He points this out to the army guy who yells to his men "The Javelin is the key." The Javelin is the anti-tank weapon they use to take the tripod down.
Question: When Tom Cruise is battling to get free of the tentacle pulling him into the ship from the cage, there is alien (presumably) writing visible on the underside of the tripod just beyond his arm and above the lights. Can someone shed light on what this may say (theories, previously suggested writer/director thoughts)?
Answer: My guess is that it could be a manufacturing symbol or name like you would see on today's construction machines. It could also be a warning like, "Caution: Hot Vent", or something along those lines. To my knowledge it is never clarified by anyone.
Question: Several other answers and corrections state that the reddish liquid sprayed by the tripods was what essentially grew the red vines. However I thought I heard someone in the film say something along the lines of "using us (i.e. blood) as fertiliser". Can someone please clarify?
Answer: Since the tripods tended to spray the red fluid shortly after pulling a human into themselves, it seems a good assumption that the red fluid is essentially blood. Given this, it seems likely that the "spore" of the vines is spread in the red fluid.
Question: In the scene at the ruined house, what is Ray doing in the closed room while his daughter is closing her eyes and singing?
Answer: Tim Robbins was shouting quite loud (and losing his mind) and Ray did not want the aliens to discover their hiding place. He therefor had no choice but to kill (or possibly beat unconscious) Robbins in order to keep his daughter safe. Rachel was told to sing so she would not hear what her father was doing.
Question: I was a little confused. Why did the aliens die? I know it had to do with micro organisms but the answer doesn't come clear to me. Can someone please explain this for me?
Answer: It's similar to how the Native Americans were decimated by smallpox and other diseases when America was colonised by Europe - They had never encountered that virus before, so they had no immunity to it whatsoever, and many of them died. The aliens would have no immunity to any diseases, or even a basic hereditary immunity to default earth viri. Basically they all caught some disease or other (maybe even a cold), and died because they had no immunity at all to it.
Question: In the scene where Tom Cruise and co. are in the tripod's 'basket', a man is sucked up into the tripod and no-one does anything, but as soon as its Cruise's turn everyone grabs him to try and help, why?
Answer: When Tom covered his daughter he noticed a grenade belt dangling from the cage. He grabbed it as he was being pulled into the tripod. When the soldier noticed Tom had the grenades he immediately grabbed Tom to pull him out, and ordered everyone to pull as well.
Question: At the end, a tripod collapses after behaving erratically for an hour, because the aliens inside were dead or dying. If so, wouldn't the tripod just stop moving and stand there because the aliens were too sick to operate it?
Answer: Depends on exactly how the disease affected the aliens. They might have entered a state of dementia and started piloting erratically, or even just have muscle spasms that knocked the controls around inside the cockpit.
Question: Near the beginning of the movie during the lightning storm Ray says "wheres the thunder?", Isn't thunder just the sound lightning makes and if you were close enough to the lightning wouldn't the sound occur at the same time as the flash?
Answer: Precisely - Ray is seeing the lightning but there is no sound of thunder at all - there is also no sound of the thunder as the lightning is getting closer too, it's just the lightning itself and that 'whooshing' sound, but the sound doesn't sound like thunder.
Question: Is it realistic to think that Manny, the garage mechanic would have NO idea of what was going on when Ray steals the van from him? After all this is probably about 20 minutes after the Tripod emerged a few blocks away. Surely news would travel faster than that! And you'd think Manny would have felt the massive tripod moving or heard the destruction.
Answer: There's no electricity, so the only way Manny could have heard was through word of mouth. The few survivors from the initial attack scattered in different directions and if any happened Manny's way, they were probably too busy running to stop to explain anything to a garage mechanic. As for his awareness of the destruction, anything he may have felt or heard he likely dismissed as further manifestations of the freak electrical storm.
Question: When all of the people are trying to get on the boat, how does a tripod just randomly come out of the water like that?
Answer: While it's never explained, there are several possibilities: as all the tripods were buried deep underground, this one may have been lodged below the lake and was just emerging. Also, a tripod could have "walked" from somewhere else, then went underwater to explore, and, attracted by the ferry's noise and movement, surfaced to investigate. It's also conceivable that, observing how ferries worked, it slipped underwater from further away and ambushed the boat, or the tripod was simply making a crossing from one shore to the other (traveling underwater if it was deep enough) and just happened upon the ferry when it did.
Question: Is there any indication as to where the aliens come from and what exactly they want?
Answer: In the original George Pal version they were Martians and the reasoning for what they were doing was never explained. In this version, its never explained where they come from, but their mission is simple, to eradicate human life from Earth, and use our bodies to fertilise the planet, probably so that they can colonise the planet for themselves.
Question: Why didn't the aliens take over earth for their own means millions of years earlier? And why send machines millions of years before any humans or life that could be considered a threat?
Answer: It's not known when the aliens sent the machines--the 'millions of years' comment was just one bystander's speculation. The machines could have been sent well after humans evolved and for whatever reason, the aliens did not journey to Earth until much later. Obviously, humans were never considered a threat--just an inconvenience to be eradicated. Because we don't know who the aliens are or how their society and technology works, many questions will remain unanswered.