The film begins with Seth, play Jeff Goldbloom in the midst of a press conference.
He invites a woman back to his lab to show off one of his latest experiments which seems a lot more industrial than the previous film. Instead of locating it in the basement of his house, it is located in an abandoned factory. The 'telepods' as he calls them, have also gone through a significant redesign from the first film.
He takes a pair of tights from the woman and places it inside a telepod and initiates the procedure.
The film gets straight into the action, skipping the murder sequence and the inspectors from the 1958 movie.
The woman turns out to be a journalist, Veronica. She broadcasts the story, but her boss doesn't believe her and refers to Seth as a 'magician'.
As would be obvious by now, Seth, unlike the main character of the first film, doesn't seem to have a family.
He explains that he's going to attempt to teleport himself. Arriving back at her apartment, Veronica meets her boss there and apparently they have been together.
Later that evening, Seth experiments with a baboon in his teleporter. The baboon has turned inside out. This film exposes body-horror to the audience in its full form, showing everything in its entirety. This paticular scene was gut-wrenching and horrid--the perfect reaction from the audience.
He then shows that he has the same set of clothes for every day of the week.
Next morning, he experiments with a raw steak on a plate which had been teleported, then cooked and a steak which had been cooked normally. The teleported stake tasted synthetic due to the fact that the computer in the teleporter hadn;t learned how to teleport flesh.
Once sgain he teleports a baboon. After teaching the computer to teleport flesh, the baboon comes out unharmed.
However, it turns out that Veronica's boss has published the story.
After talking to the experimental baboon about Veronica, it shoos away a fly, perhaps the only reference to a fly in the first part of the film, unlike the older film, which constantly referenced flies. It flies inside with Seth, but he seems to come out the other side unharmed.
Unlike the first film, we actually see the teleportation take place with the fly and Seth.
We then see that the transformation into a fly-human hybrid is beginning to take place with the growing of small hairs on his back. We also see that he has grown immensly strong and athletic.
Later in a scene in a cafe, we notice that he's grown a taste for suger in his coffee and Veronica begins to notice the hairs growing from his back. Also, he has been extremely active and unable to sleep. After an argument with Veronica, he storms out of the lab
Finally, in another body-horror scene, he snaps a man;s arm duting an arm-wrestling contest in a bar. This is another example of body-horror rife in this film. He takes the brawler's wife to his laboratory for the night, during which the camera pans to the view of the bristles on his back.
He tries to force her through the teleporter, but Veronica interjects.
These scenes give the impression of more conflict between his human anf fly conciousness such as punching walls.
The transformation also has scenes of body horror--he peels off his finger nails and his teeth fall out.
We then find out that the fly and hum are fused on a genetic level. There isn't much mention of the fly post-teleportation unlike the 1958 film.
More body-horror as we see that Seth has been further transformed. His skin is slimey and riddled with boils. His ear also falls off and be pukes over his food to digest it like flies do. He also uses a pair of canes to walk on.
As the movie progresses, we see him transforming more and more into a fly-human hybrid. His skin is further engrossed with boils and he can also walk on walls and ceilings.
As a seemingly unrelated note in the movie, we find out that Veronica is pregnant with Seth's child. More body horror as we see the it is in fact an enormous maggot. Veronica wakes up from the horrible dream.
We find Seth trying to set a goal on the computer, but it cannot recognize his voice and his teeth fall out--yet more bodily horror.
We also see Seth's behaviour slowly grow more and more inselct-like with erratic, twitchy movements and a somewhat more eccentric personality.
Seth overhears Veronica protesting that she doesn't want his baby, which breaks his heart. Veronica wants an abortion. Suddenly, the mutant Seth bursts in and whisks her off.
Veronica's boss enters Seth's lab and loads a gun. Seth pounces him and dissolves his foot and hand before Veronica interjects him from devouring him. Seth then tries to convince her to go into the teleporter with him, but she objects and rips off his jaw as he finally transforms into a monsterous fly. Veronica's boss loads the gun and uses it as a crutch to lift himself up before finally shooting the porter. The monsterous seth breaks out and is only teleported halfway, rendering the teleportation useless. The half-teleported Seth comes out and points her gun to his head willingly. Remosefully, she shoots, killing him.