When Jim goes to receive his instructions for the mission, he gets inside a 2 door Rambler American. Once inside, the car has changed to a 4 door Plymouth Valiant.
When Rollin Hand is preparing Cinnamon Carter to look like Anna Rojak - The Anna Rojak appliance on the table is quite realistic, including eyelids and natural coloration. However after lifting it and holding against Cinnamon's face, it now has much less color, and no eyelids. The original appliance was Lee Meriwether's face surrounded by a terry cloth cutout. "Hanging" just above and to the right of Lee Meriwether face is Barbara Bain's face, also being used as a mask.
The second time Jim beeps the car horn to get Barney's attention, he waves and Barney waves back in the distance. Then, in a closer view of Barney, he again raises his hand and waves back.
When Jim gets into the parked car in the first scene, he sits in the passenger seat yet when the camera cuts to the inside view, he is in the driver's seat.
Colonel Ziegler reports that "Test expectation indicate that the almost 200 percent decrease in size and weight of the weapon...". A 200 percent decrease is impossible (That's the IMF's job). A 100% decrease would reduce it to nothing.
Two lab techs in white coats are seen pulling the second stage of the missile on some type of small mine shaft rail cart, with one armed guard escorting them. A missile of such importance would be too valuable to have just one armed guard in escort, especially when it is outside as in this case.
The guard that operates the gate leading to the laboratory cannot see who gets off the elevator. Yet he operates the gate when he hears someone coming. The control is also easily accessible from the other side by reaching through the bars.
Rooftop shots reveal many palm trees of Southern California. There are no palm trees in Eastern Block countries.
Willy uses a winch to lower himself down through an air shaft. When he looks up at the apparatus, the rope paying off the reel is wobbling around loosely, indicating there is no actual weight on the line.
When Colonel Ziegler comes for a meeting with the General, as he exits his car, a blue Bell System sign on the building is visible behind him, in spite of the "Stat Telefon" truck with logo emblem.
The stenographer at the meeting with the General isn't recording anything. She's often not even moving her fingers as they are speaking.
While testing the hovercraft at the briefing, strings can be seen suspending it.
After Ventlos gets in his car and checks out the pictures of Ziegler, he drives away. As he does so, several men (presumably crew members) are seen reflected in the car's rear window.
The Hollywood sign on the hillside and the Griffith observatory are visible in the distance.
When Cinnamon enters the bunker, and all later times, except as Anna, she gives her surname as Vladislav. Others also use the same name. However, women in Russia and other Eastern Bloc countries, have their surnames ending in "a." So, her name should've been Vladislava.