Seeking alien invasion movie

Question

I rented an alien invasion movie in the mid-90s that I recall as being pretty good. I'd like to see it again, but I'm a little short on details. Really, I have only these:

• The aliens impersonate humans.

• A female scientist explains how some aliens she'd met felt wrong to her. When she meets men for the first time, she says, they invariably check out her body as they shake hands, however fleetingly. The aliens don't do it at all.

• Some scientists examine a map on which the incidences of alien replacements/abductions/whatever have been overlaid. It looks like an shapeless blob at first, but someone realizes a river runs through the blob, and the shape can be explained by some alien presence moving downriver, spreading the infection (or whatever) outward at a constant speed as it goes.

At the time I saw the movie (mid 90s), I remember thinking that it had been made within the previous 5-10 years or so. On the basis of very little evidence I later guessed that it might have been been the 1978 remake of "Invasion of the Body Snatchers," despite being outside of the expected time range. However, I just finished watching that movie, and it definitely isn't the one.

Answer 1

This sounds like the 1994 movie version of The Puppet Masters.

The original book, by Robert A. Heinlein, was first published in 1951. If you want spoilers, here's the wiki entry.

from the IMDB page:

The Earth is invaded by alien "slugs" that ride on people's backs and control their minds.

Strange aliens land in the Midwest, taking over people's minds in order to spread their dominion. Sam Nivens and Andrew Nivens, aided by Mary Sefton, are part of a government agency who must stop the the aliens before the aliens get to them...

I don't recall if the scene where the woman explains how the alien-infected men don't react to her is in the movie, but here's the scene from the book:

    “Both the state sergeant and the two boys. When I use the sweet-little-bundle-of-sex routine, something should happen. Nothing did.”
    “They were all attentive,” I objected.
    “You don’t understand. You can’t understand-but I know. I always know. Something was wrong with them. They were dead inside. Harem guards, if you know what I mean.”

Answer 2

The storyline sounds very similar to the "Invasion of the Body Snatchers". Since you say the 1978 movie isn't it, it may well be another movie with largely the same premise (although not a remake), "Body Snatchers" (1993). I haven't seen this movie, but the storyline seems to fit, as does the timeframe. The Wikipedia plot summary does mention a river as the source of alien pods.