Continuity mistake: The stewardess comes into the cockpit and holds the clipboard between her folded hands. In the next shot she's holding it with her left hand. (00:28:25)
Visible crew/equipment: As a prop they use a 50' style radio microphone strapped to the co-pilot's chest. (00:04:45)
Factual error: The gunpowder made in the 1950's didn't produce the clouds of smoke we see whenever the police fire their weapons, but those of the 1870's did. Ed must have nicked some ammo from the Lone Ranger's property master, eh?
Continuity mistake: At the grave yard it's pitch black out but you can see the reflection of a studio light in the police car windshield. (00:57:15)
Other mistake: During the first funeral, the priest only reads the bible for himself and says nothing to the other people. (00:02:35)
Continuity mistake: The stewardess says to the pilot, "I'll be right back," as she touches him with her right hand. In the next shot she's nowhere near him. (00:29:15)
Revealing mistake: Why are all of the space ships the same exact size as the planet?
Continuity mistake: Tor Johnson walks to his left past the mausoleum as the ghoul comes out and follows him. He never turns around but two shots later if you look at the head stones, he comes up to the same place again. (00:14:45)
Deliberate mistake: When the pilots are flying in the airplane there's a strange device above the co-pilots head. Later in the movie we see this same prop used again inside of the spaceship as the alien beauty Tanna opens up the hatch. (00:04:35 - 00:36:30)
Revealing mistake: When somebody walks in the cemetery, it happens often that the grass slides under their feet, like fake grass. (00:35:55)
Revealing mistake: When the flying saucers are passing over Hollywood and Washington D.C., there's some shots where you can see their shadows on the fake sky. (00:18:15)
Deliberate mistake: As Paula is chased by the ghoul into the cemetery the shots continuously change between night and day throughout the entire scene. (00:32:35)
Visible crew/equipment: When the officers in Washington are listening to the alien message, there's a shot where you can see the shadow of the crew on the desk, just before the message has finished. (00:44:55)
Revealing mistake: Inside the alien spacecraft a battery operated blinking traffic caution signal is used as a prop from another world. (01:04:50)
Continuity mistake: Bela Lugosi's wife was buried under ground and we see the gravediggers cover the casket. In the next shot we see her above ground near the mausoleum. (00:08:15)
Continuity mistake: As Tor Johnson rises from the dead there's dirt all over his body but none on his face or head. (00:32:50)
Revealing mistake: The inside of the spacecraft is populated with electronic equipment sitting on tables. You can easily identify a Hallicrafters short-wave receiver which the alien tries to smash on Jeff Trent's head. In the B&W version, you can even see manufacturer labels on the front of the units. They are missing in the colorized version.
Revealing mistake: As the saucer flies over the graveyard, Tor Johnson's shadow can be seen on the studio wall behind him. (00:13:20)
Continuity mistake: Tor Johnson sits in the front seat of the squad car at the police station. In the next shot of them arriving at the cemetery he's sitting in the backseat. (00:09:20)
Plot hole: The aliens' plan ("plan 9") is deeply flawed. The aliens resurrect the dead to make earth people accept the aliens' existence. However when Eros reports to his leader, he says that "none of the risen have been seen." What's the point of raising the dead if they aren't seen anyway? And while later, yes, the old man enters a dwelling and is by everybody, anything before that was just a huge waste of time on the aliens' part, making the first phase of the plan completely senseless.
