When Kirk addresses the crew over the ship's intercom, the first reaction shot among the crew shows Mr. Leslie, wearing a gold officer's tunic, walking through the corridor with Lieutenant Brent. However, the second reaction shot of the same speech shows him in Engineering, wearing a red jumpsuit.
When Gary Seven first beams aboard the Enterprise, there's a brief shot of Scotty at the transporter with no sideburns (footage from early season 1). When Scotty is shown again, his sideburns are pointed.
The same people can be seen passing - respectively - Kirk and Spock, and Roberta on her way into work, on four separate occasions (once in the same but split scene), going back and forth. The part of the walkway, however, is roughly the same on all occasions.
When Scotty is looking for Mister Seven, some of the shots of the Saturn rocket are of when it's being transported to the launch pad.
The outside view of the gantry elevator shows that it has solid metal walls up to about 3 feet, and then grating to the top, but, when the view changes to within it, the grating is floor to ceiling. (It's also a different patterned grating.)
When launch control announces that the rocket has reached 1,000 feet, it is shown already deviating from the vertical on a downrange trajectory. This does not happen until the rocket is much higher than that. Since the Saturn V is 365 feet tall, at an altitude of 1,000 feet, it is less than three times its height above the ground, and does not appear to be at a great height in relative terms. Furthermore, if the rocket had deviated that far from the vertical at only 1,000 feet, it probably would have crashed.
Security shown at the Base is civilian. Cape Canaveral is a USAF base and all security is from Air Force personnel.
When Mr Seven first encounters the security guard, he addresses him as "Sergeant" and then moments later identifies him as "Sergeant Lipton". However, the guard is wearing collar tab insignia for a corporal.
The location of the control electronics in the warhead make no sense. They would not be placed in such an accessible location, protected by such a flimsy cover.
Unless this episode takes place in an alternate timeline, the description of the nuclear threat during the Cold War that Spock gives is historically and technologically inaccurate. The US's nuclear weapons at the time (1968) comprised land- and submarine-based intercontinental ballistic missiles (ICBMs), along with more traditional nuclear bombs carried by bombers and fighter planes.
The Soviet Union developed a sort of launch system that orbited the planet, but despite expensive and highly secretive attempts by both US and Soviet governments to weaponize space, an effective space-based weapons system was never effectively deployed.
The Soviet Union developed a sort of launch system that orbited the planet, but despite expensive and highly secretive attempts by both US and Soviet governments to weaponize space, an effective space-based weapons system was never effectively deployed.
During the teaser, wide shots of the bridge show Lt. Leslie sitting at his station. However, during closeups of Sulu, the chair is vacant.
(at around 35 mins) When Roberta is trying to open the safe "transporter" in Gary Seven's office, you can see the string attached to the door used to pull it open, when she is turning the knobs.
The black markings on the rocket change from shot to shot, because some views are of the prototype facilities checkout vehicle rather than an actual rocket. On the prototype the black stripes on the first stage are longer and are linked at the top by a black ring. Additionally, the prototype third stage has four black panels at the top and a ring at the bottom: the version seen lifting off has only a black ring at the top.
The images that Scott is supposedly getting by bouncing a signal off an old weather satellite simply would not give a variety of angles as is seen here. Neither the satellite nor the Enterprise is moving fast enough in relation to the Saturn rocket on the launch pad to give a rotational series of images like those seen.
As the gantry elevator rises with Gary Seven, a shadow of the grating wall is cast on the floor of the elevator, but, as the elevator car passes girders, their shadows should also be cast on the floor, although they are not. (This shows that the passing girders are simply backdrops being scrolled by.)
After Mr Scott gives his report via the monitor in the briefing room, his image blanks out just before Kirk turns off the monitor.
When Kirk fires the phaser at Seven in the transporter room, it makes a flash, but the animators neglected to draw in the phaser beam.
A hand can be seen reaching over and adjusting the light display on Mr. Seven's computer.
When she calls the police, Roberta gives her address as 811 East 68th Street, Apartment 12B. The street address would put the apartment somewhere in the East River. While the apartment number is possible, it puts the ceiling on the low side for Manhattan; a 12th floor Manhattan apartment with average ceiling height would be closer to 40 meters off the ground than the 30 Scotty says it is earlier in the episode.
When Spock is trying to subdue Roberta, he apparently forgets the Vulcan neck pinch.
Gary Seven is able to fight off five Enterprise men and a Vulcan neck pinch in the transporter room, but Roberta stuns him with a simple blow to the head with a metal cigarette case.
For some unknown reason, Gary Seven is never searched by security when placed in the brig, which then allows him to casually withdraw the device he used to break the force field from his inside coat pocket. He is even allowed to keep his wristwatch.
Gary Seven is a human who has apparently been enhanced in some way during his time on the alien planet. And yet, he's incredibly slow to recognize that Miss Lincoln is not an agent like him.
When Gary Seven beams aboard the ship Captain Kirk introduces the Enterprise as the United Spaceship Enterprise, not the United Starship Enterprise.