Once you see the line-up of films, you might see where this is going. I have seen much speculation about people being a bit off, or different after recent events. And it made me think of a number of films that fit the bill.
Invasion of the body snatchers (1955 and 1978) – I haven’t seen either but the plot sounds great and I wished I had. It’s as it sounds, but how they snatch you is the interesting part. The human is put to sleep, and a replica of them grows in a pod nearby. Once the pod is fully formed, the human turns to dust and the replica is now in its place. Human looking, but void of emotions.
V (original series 1983) – only seen a few episodes of this, but it was enough. They look like us, round up our doctors and scientists who speak like us, then take us over.
Dark City (1998) – this one pops up a lot because it’s got it all. But for this theme it’s the reveal to the confused main character about what they are. The picture and quote are from this film. “We use your dead as vessels”.
They Live (1988) – A classic and of course would be in this list. Human looking beings infiltrating society and hiding a nefarious plan.
Village of the Damned (1960) – Same theme, but with children, so extra creepy.
Alien (1978) – Only because there is a time period after exposure with the characters act like normal humans. Making the difference undetected to their fellow normal humans. That seems to be the important bit in all these films, that we just can’t tell. Or if we can, we don’t know why.
The Thing (1982) – This one a shape-shifter and appearing just like the person you know. This film I suspect terrified more people than I care to imagine.
Again, there are countless others that will be about possession, infection, abduction, being altered in some way by some alternative species. So that you look like you, but you aren’t you. And infiltrating, conquering/massacring and controlling humanity seems to be running theme in all of them. Is it because it’s just an idea? A natural fear we collectively have? Or is it because deep down we know something isn’t quite right?