Plot hole: Patrick Redfern needs someone to be in the boat with him to corroborate his and his wife's deception and be his alibi. That is whole point of his wife lying on beach - he gets this when taking Myra for a ride - but it was portrayed as a random ride she got, he did not intend or plan giving her a ride, he did not see her loitering near the boat, or even in view of him untying the boat. Even if that was intention in the story for him to be seen ready to cast off, the movie viewers did not see her viewing him, only her appearing just before he was set to cast off. Without someone with him the whole deception would not work, he would have no alibi, he could have killed Arlena unseen.
Plot hole: As the gun-toting Norseman approaches the buildings, Garry smashes the single-pane window with his handgun. It is inconceivable that the glazing in a structure near the South Pole would be single-pane glass, that would provide minimal insulation and which could be broken so easily.
Plot hole: We see Jason get his outfit from Harold's clothes line. Yet in Chris's flashback Jason has these same clothes already on.
Suggested correction: I went and looked at both Chris version of Jason and Jason in the recent Part III. The Part III Jason outfit in Chris version has a lot darker clothes. Same style, just darker. That type of clothing is very similar though.
Plot hole: Why doesn't Reliant know that Khan is exiled here? The Federation is so terrified and opposed to genetic engineering that it's still illegal 300 years after Khan. So why is there no warning along with the data on the Ceti Alpha system? Kirk logged what happened with Khan and his solution of marooning him. Starships use nav data to navigate star systems. Ceti Alpha 6 exploded, yet the helmsman or computer never noticed that there is one less planet than there was when Kirk was there? There is no debris from the explosion? Ceti Alpha 5 is the exact same size and was conveniently blown into the exact same orbit as Ceti Alpha 6 used to have? So there is nothing whatsoever to make the crew even suspect that it's not 6? Enterprise would have to have scanned the planets in the system to know that one was habitable for Khan. Did Ceti Alpha 6's destruction somehow magically turn Ceti Alpha 5 into its exact duplicate? If Starfleet ships have been there to map after Ceti Alpha 6 exploded, none of them bothered to check on the exiles? Pretty callous for Starfleet, don't you think? With the technology and amounts of information available to Starfleet vessels, there is NO logical reason for the Reliant to think that this planet is Ceti Alpha 6. Finally, would the Federation be willing to test a device whose exact effects will be unknown on a planet so close to another inhabited one? (00:21:00)
Suggested correction: The answer is yes: against all known laws of science, the inexplicable explosion of Ceti Alpha VI led to Ceti Alpha V conveniently taking its orbit and making it easy to mistake for its former sister planet. A mistake would've been to give an explanation that can be debunked. By leaving it to "somehow" the movie leaves it open to a million possible rationalizations. You can even make a whole other story about the crazy circumstances that led to this incredible result.
Plot hole: In the locker room scene after Rocky's loss to Clubber, we see Mickey take his last breath and Rocky lays his head on him and starts crying. Doctors were present, wouldn't some effort of CPR or resuscitation have at least been performed?
Plot hole: When Rambo hijacks the Army truck, he throws out the driver, Robert A. and continues driving down the one-lane dirt road in the same direction. When Robert A. hits the ground, he immediately pops up and runs the opposite direction, away from where the truck is driving. A couple of shots later, we see a behind view of Robert A. running. It turns out that it is the driver's view from a Sheriff's vehicle. How could a car, especially a Sheriff's squad car, possibly come from that direction since it was a one-way road? And how could that same officer not see that the man driving the truck was Rambo?
Suggested correction: It isn't shown that no other roads join that one. It's therefore reasonable to assume the police car joined that road from a branch / connecting road and didn't encounter the truck.
Plot hole: In what appears to be at least an hour or so after curfew is put in effect, Challis goes to a liquor store. Even if he didn't know about the curfew, why would the liquor store still be open?
Plot hole: "Dorothy Michaels" does not exist, but suddenly becomes famous. It is simply not feasible that nobody looks into her background! Not one single print or television reporter is interested in her life story? Nobody has ever wondered where she came from, has checked into what other roles she had played, or has expressed interest in her personal life? That's impossible.
Plot hole: When Ching and Jen Moo are confronted by the God Skills Society at the Sun Family Temple, there are three disciples appearing behind the master. But only two of then (the long-haired man, and then the monk) are seen entering the fight; the third one suddenly appears as a yellow-clad corpse at the entrance stairs as Ching fights the long-haired man.
Plot hole: In the scene in Hess's office, he agrees to save Sophie's son and remove him from the concentration camp. He also tells Sophie that he'll bring her son to see her the next day. In the very next scene, Sophie attempts to steal Hess's daughter's radio which would completely jeopardize the saving of her son if she was caught. It is unlikely that she would jeopardize the wonderful situation she arranged for her son, by stealing a radio. Later, Hess does not save her son, but Sophie didn't know this would happen, so she would not have attempted to steal the radio at that time.
Plot hole: We learn in the film that Cat People must kill a human in order to return to their human form. However, after becoming a cat at the swimming pool and terrorising Alice, Irena becomes human again without making a kill (the only other person at the closed pool is alive and well at the end of the scene - we know Alice has not imagined the presence of the cat because of her shredded clothes). (01:31:00)
Plot hole: Frank Ochoa told miss Nicole that Paul killed 9 people in New York when in fact he killed 10. (00:47:00)
Plot hole: In the very beginning at the mall, where the older guy comes in to the pizza shop and sits in Stacy's section - the co-worker says "she's not even in high school yet." First of all, the school she's at is "Ridgemont High", and secondly, if she wasn't in high school (which would mean she would be younger than 15 at least) - how could she have a job, where the minimum age is at least 15? Even by mall standards, it's doubtful they would hire someone who is 14.
Suggested correction: In the 80s, high schools in most California areas were 10th through 12th grade (not 9th-12th like they are today). So many students DID enter high school then at 15.
