All the succeeding versions of Invasion of the Body Snatchers have been weaker than the ones which came before, but they've all had interesting additions to the basic story of the pods taking over people.
The original (1956 with Kevin McCarthy) was the best because it was a low-budget film noir that didn't take itself too seriously. The Philip Kaufman remake in 1978 set in San Francisco anticipated the AIDS/STD crisis that was just around the corner. Abel Ferrara's version Body Snatchers (1993), set on an Army post, gave us a look at what happens when a society is increasingly militarized without wide scale involvement in the military by civilians for a temporary term of service, the way Americans experienced World War II.
The Invasion starring Nicole Kidman is the least interesting yet, but even it has a couple of intriguing ideas. I get the feeling it was intended to say some halfway serious things about the United States and its place in the world before a glamorous movie star got involved.
Pills have replaced pods in this version of the story.
Psychiatrist Carol Bennell (Kidman) prescribes a change in medication when a woman in an abusive marriage reports that her husband has become much calmer, except for strangling the dog when it growled at him.
Later one of the newly infected asks Bennell if she can give him a pill to prevent a Darfur, or a New Orleans.
Before the alien infection arrives on Earth, Bennell is caught between her ex-husband and her platonic boyfriend. We see both men before and after they're infected. Unlike previous versions of the story, people aren't killed and replaced by duplicates grown from pods, they are just transformed by an infection into a joint human-alien entity.
These monsters aren't the emotionless pods of previous invasions. One old man, after he's transformed, comes back to his wife and begs her to join him. His desire for the woman he's loved for decades seems real.
Bennell's ex-husband is a jerk before and after he's infected, and her boyfriend is the same calm rational man he was before. This invasion of the body snatchers doesn't really result in losing your identity. The peace that breaks out all over the world is almost as ludicrous as in the 1952 B movie with Peter Graves, Red Planet Mars, when God speaks from Mars.
I think the people who conceived this film wanted us to consider that maybe we should allow the infection to change us.
There's one moment at the climax, when it looks like Bennell and her son (who's immune to the infection) can't escape, when she considers surrendering. But they won't allow her immune son to survive and risk the new order. So she blasts away.
It's no surprise that salvation comes from Fort Detrick, where the scientists have been working on a drug (of course!) to reverse the infection.
The world goes back to normal, but the movie doesn't tell us that the scientists at Fort Detrick have kept a sample of the alien substance and are working on a way to turn it into a weapon. If that's the sequel to this movie, it may be the most honest version of Invasion of the Body Snatchers yet.